EGO 56V ARC Lithium Battery Repair

[@somethingsomeone5440]

Nice! I bought a couple dead batteries off ebay in the hope of using parts between the two to make one good one. I had one that flashed green after jump starting the battery. It had 3 or 4 failed cells. The other packs front panel was dead. Checked the cells and every one of them was 3.7v for the win! I swapped over the flashing front and that packed worked perfectly. Then I watched this video and got excited that I might be able to get a fully functional pack. I removed the silicone around that transistor and mine is shorted in the same manor. I'll be ordering the transistor after I click send. Thanks man you're awesome!

[@ThriftyToolShed]

Awesome, great job! Thanks for your comment!

[@michaelbirchall2247]

How did you get on with this. I've just ordered my part for a fix.

[@somethingsomeone5440]

@@michaelbirchall2247 it’s was a success! I’ve been I’m using it for I guess a year now. I have two of the same size packs that I alternate between for the weed eater. At this point I’m really not sure which pack I fixed and which came with it. They perform the same.

[@michaelbirchall2247]

@@somethingsomeone5440 that's great. I've also just fixed mine the same way. It's a great feeling.

[@ngottron1226]

Thanks for the very detailed video!! My 5.0 battery was doing the exact same thing. After spending ~1 hr viewing this video, I went directly to the Q12 transistor (it tested bad as in the video), replaced it, and voila! My battery is working again. Thanks for helping me save $200!

[@ThriftyToolShed]

Awesome, Great job! Great information also, I have not heard of 5ah packs having the same issue, that's great to know. Thanks for your comment!

[@jdoge13]

Worked exactly as described. Cost $15 to get the chips shipped in. Thanks for the effort troubleshooting this and saving us replacing an otherwise functional battery!

[@NZSpides]

Ive had my pack show this issue for some months now, and have been just charging the pack to keep it from going flat. After seeing how easy it is to fix this issue, I've ordered some of the chips and will replace it when they arrive - I'll be sure to come back and comment to let you know how it goes. Awesome teardown and fault finding. This is what the right to repair is all about.

[@ThriftyToolShed]

Exactly, best of luck to ya! Thanks for sharing!

[@tonys4396]

THE BANG TRICK WORKED .SO glad I saw the comments about banging the battery from about a foot off the ground and dropping it. IT WORKED I had THREE bad batteries. ALL THREE have been working GREAT since May and I recharge and use the OFTEN. HOLY GUACAMOLE. Those three bad ones were here for over a year. I bought two news ones for 200 bucks a piece but something told me NOT to throw those bad ones out. THREE bad batteries now working PERFECTLY for five months with CONSTANT charging. I have the lawn mower, leaf blower and snow blower and I use the blower daily and the lawn mower once per week. HUGE area. SO glad I was the comments about BANGING the batteries. THANK YOU THANK YOU THANK YOU

[@arie1293]

Thank you so much for posting this! I replaced the cells on a dead pack I bought off eBay and when I hooked up the BMS it had the same symptom. Found this video and went straight to Q12 and it was shorted as well. Replaced with the part you linked to on eBay and the pack is no longer stuck in maintenance drain mode.

[@ThriftyToolShed]

Awesome job, thanks for sharing!

[@zaccravens757]

I fixed my 2.5 Ahr by replacing Q12 after watching this video! Thanks so much for taking the time to post!

[@ThriftyToolShed]

Zac Cravens, That's great! Glad it helped and thanks for your comment!

[@georgezychek9239]

Great video...thanks! I stopped an earlier attempt at repairing the pack when I saw the potting, but you pushed a little harder and got it done. Nice to see component level trouble shooting by someone who knows what they are doing. Thanks again.

[@ThriftyToolShed]

Thanks for your comment!

[@megadosmegados609]

Awesome video! I was hesitant to pick away the potting material, but then happened upon your video, and you convinced me. Also, you saved me a lot of testing, and ultimately, my battery! Thank you.

[@MegaNumero6]

Just saved my 7.5Ah battery with your help!!! Many thanks

[@ThriftyToolShed]

Awesome job! Thanks for sharing!

[@MegaNumero6]

@@ThriftyToolShed In fact, I didn't do "an awesome job" since my iron was too hot and managed to make one of the coppper trace on the board to detach :D I had to refit a litle wire to redo the circuit trace :D.... BUT IT WORKS! I am so happy :)

[@heathicusmaximus8170]

I can replace a carburetor, but troubleshooting one of these boards is way beyond my skillset. One reason that's holding me back from getting an electric mower is that I wouldn't know how to fix it. Plus I don't have the nifty bench tools. Glad someone is able to do this!

[@mitchphillips3034]

Thank you very much. My battery was 3 years and 1 month old and Ego wasn't going to do anything for me. I fixed my 2.5 AH battery by replacing Q12 after watching this video! Fun to watch and very helpful....

[@ThriftyToolShed]

Excellent job. Thanks so much for your comment!

[@mitchphillips3034]

@@ThriftyToolShed I had charged the battery before doing the repair and finally got around to using the battery until it wasn't driving my string trimmer anymore. However, my charger seems to think it's still fully charged and won't charge the battery. Pushing the button and still shows green. Any suggestions?

[@ThriftyToolShed]

I have not had that issue by just replacing Q12. What is the voltage reading of the pack at the terminals?

[@mitchphillips3034]

@@ThriftyToolShed I'm reading 46.6V. But I still get a green light when I push the button...

[@ThriftyToolShed]

@@mitchphillips3034 At 46.6V the average of the 14 sets in series should be 3.32V so the only thing I would know to try is see if all cells are balanced well. If one set is still around 4V or so it may show it's fully charged because one set is still high enough. Checking the balance is all I can think of, other than that it's a problem with the BMS board thinking it's that way.

[@darrinanddonna]

Wow ! Totally blown away by how you have fixed the battery management board ! Thanks for taking the time to do this :)

[@ThriftyToolShed]

Darrin Ray, Hope it helps. Thanks for your comment!

[@darrinanddonna]

How’s it going 2 years on ? My 7.5 amp just started flashing yellow when you press the button :( I don’t know what this code means.

[@danbranch1885]

That was excellent good troubleshooting and repair, the soldering technique and use of the solder-sucker to clean the excess was awesome. Good job sir.

[@ThriftyToolShed]

Thank you sir for your comment!

[@lmorrison17]

NICE JOB! I found this vid because I got one of these out of the recycle bin at home depot to recover the cells. They were all at .5v. I started charging a few at very low current just now but they are taking charge. Need more to test them for impedance and capacity to see if they are recoverable. If you want the board out of it your welcome to it. But I did snip the balance leads, thermistor leads and main current wires right at the cells. Thank you for the time and trouble you took to share this with everyone.

[@pashko90]

how did you got it? In Los Angeles they are not allowing you to go thru a bin...

[@ThriftyToolShed]

Hi, I also have got several packs from the recycle bin. I have asked the Manager at our local Home Depot and He was fine with me going through looking for packs. I am sure it could vary store to store and even manager to manager...

[@lmorrison17]

@@pashko90 I goto lowes and home depot. Some store let you have them some dont. One store it depends on who is on duty at the CS desk. So I have learned when not to go to that store.

[@pashko90]

@@lmorrison17 What is CS stands for? cant figure it out.

[@ThriftyToolShed]

I am voting... Customer Service.

[@michaeljanisse4824]

Thanks for the thorough video. I have one 2.5 aH battery that’s in need of repair. The video walked through the diagnostic steps as well as what to be looking for. I appreciate the work you put into this. I like your PWB holder. That provided stability when aiming for the test points. I have 6-7.5aH batteries, two of which are aging and may be ready for some TLC soon. Take care!

[@jmm1000]

Absolutely fantastic work. What generous contribution this clip is!!

[@ThriftyToolShed]

jmm1000, Thank you for your comment. So glad you found it helpful.

[@mosfet500]

Nice job. A couple of things, I always check power components first. If a uC is bad there's not much you can do and low power controllers don't go bad that often. Also when you solder components it's best to clean all the solder off the board after removing the component and then, with a clean board, place the component and solder one small tap. This way you can adjust the component to sit correctly in place by slight adjustments. You want the component to sit flush on the board and when you add solder to all the tabs before placing the component you cant't do that. Try it you'll see what I mean and you'll use less heat in the end. Good trouble shooting! I've been doing this over 50 years and I use basically the same procedure. I've trouble shot everything from top secret military main frame computers to radar systems to audio equipment. All with the same procedure.

[@ThriftyToolShed]

Thanks for your comment. I appreciate your vast knowledge and experience.

[@lorenzog2156]

What a great fault finding tutorial! I’ve just had a brand new 2.5Ah battery delivered and it was dead on arrival. They’ve now sent me a new battery and I’ve started investigating what went wrong with the dead battery. I may have the same issue. After disassembling the battery and removing all the grey goo I found a lot of black soot around the same area as Q12 on the board. I’ll do some more fault finding and see if I have the same issue. All my cells were down to 0.5V each. Thanks so much for the informative video. I would’ve been lost without it. I’ll report back if I can identify my problem.

[@lorenzog2156]

I’ve done some more work on the circuit board. I have the new model BMS without much info on the green side of the PCB. I think the Q12 MOSFET is shorted. I’ll find out more when I remove it from the board. The larger SMD capacitor just near Q12 has blown and needs replacement as well. You don’t happen to know what capacitance it’s meant to be? If not, do you know any way to find out?

[@ThriftyToolShed]

Hi, I don't have much experience with the newer 3rd Gen boards at all. I have one video on the 3rd Gen board and it did not go as planned 🙈. I did discuss some differences in them and the larger SMD electrolytic caps are not exactly the same. Not sure about the ceramic caps. Even though the only 3rd gen board I have is faulty I can try to measure the value of mine if you let me know which one it is by relation to other components or if you wish to share a picture through my channels Facebook page.

[@lorenzog2156]

It’s the largest yellow/brown SMD capacitor on the whole board. It’s right next to Q12 between Q12 and the 8 pin connector going to the battery 4 blade connector. I don’t use FB often but I’ll try hop on and send you something.

[@ThriftyToolShed]

If it is the one just on the right side of Q12, I read 2uF in circuit on mine. This is the BMS that is faulty that I showed in video below, so it's all I have to go by. Hope it helps. kzbin.info/www/bejne/qWiQhmmGibuAa5o

[@lorenzog2156]

@@ThriftyToolShed thanks so much!! I think my board is different again. I’ll take a photo and send it to you on FB. I’ll go get this capacitor and MOSFET and let you know how it goes. Really appreciate the help.

[@georgeavargas3351]

Great work I love this video. I have a lot to learn. TY for sharing your knowledge

[@OKBAOK]

I have the same problem blinking red not holding charge might be the same issue but at lease I have something to start. Good thing when my battery had an issue still under warranty and Ego replace it and they just told me I can keep my bad one so by this repair fix I probably get the bad one work again as you know this battery cost a lot. Thanks for uploading the two videos.. Will update when I tackle my battery. God Bless you..

[@ThriftyToolShed]

Awesome, yes I do appreciate EGO letting us recycle the battery. What better way to recycle than a simple fix! I do know the gen2 batteries are coming with the updated BMS and does have the fuel gauge like we have asked for. Thanks for your comment! And God Bless you as well!

[@tpeele2001]

Thanks for sharing this! I was able to repair my 2.5 battery that was flashing green.

[@ThriftyToolShed]

Timothy Peele, Glad to hear that. Thanks for your comment!

[@nickj3368]

Excellent work my friend, very well done.

[@DarryPhillips]

Thanks for the info! Appreciate what you do!

[@rcrick00]

Another very fine video. You are ovouisly a very good electronic tech. I will be using your videos when I open up my Defective Ego battery. Different symptoms though. Thanks !

[@jackhammer7428]

Thank you for the great and in depth tutorial. The battery that came with my trimmer just starting flashing green this past weekend and I couldn't find anything about it until I found your video. It's less than a year old so I'm definitely going to contact EGO first and go from there.

[@Tubavagyok]

Thank you very much! Very detailed and great video. Not easy to fix but followed steps it did work

[@ThriftyToolShed]

Excellent work! Thanks for sharing.

[@leslarson2642]

great video. working on a 5.0 ah for a friend. fortunately appears to be only a cell imbalance. the age of the battery has decreased its capacity to about 60%.

[@ThriftyToolShed]

Happens for sure! Thanks for sharing!

[@vd9300]

Great work for trouble shooting as well as video instruction! I have the same issue with my battery. Will give a try. Thanks,

[@toolshopguy2080]

Great Video! Helps a ton. U seem to be the only other one that's had this blinking green light issue.

[@ThriftyToolShed]

Thanks for your comment!

[@jesseshepherd2061]

@@ThriftyToolShed I got it on both of my battery's about 6 months apart. They were both under 2 years old. Ego said they would replace if I could provide proof of purchase and of course I don't still have the receipt from 2 years ago. Makes me really wonder about buying another ego product.

[@ThriftyToolShed]

@@jesseshepherd2061, I understand. I don't keep receipts the best either. I was lucky that I had registered mine right after I bought them and still had receipts. Still, seems like they would have tried to work with you!

[@OKBAOK]

Thrifty Tool Shed just a tip. Take a picture of your receipt from cellphone as soon as you have it in your hand then you can toss your paper receipt Lol. I do that as an habit. Because I'm having problem finding my receipt one day that I need to return something. 🙂

[@ThriftyToolShed]

@@OKBAOK, Very true. I do that now also on larger purchased if they do not email the receipt, I like it when they do that as well!

[@TranTek]

What an awesome tutorial i want to take a course from this guy, design is easier than trouble shooting

[@ThriftyToolShed]

Hung Tran, thanks so much for your kind comment. I have started a series called electronics on your level. I know it started slow but I hope to build it up to board troubleshooting!

[@TranTek]

Thrifty Tool Shed thank you i have a very new ridgid 12v drill two of batteries simply won’t charge and home depot or ridgid won’t do anything about it i will learn and try to figure it out what is wrong with them ? or even ship to you so you can do video on them

[@ThriftyToolShed]

Hung Tran, man if they Ridgid, home Depot really should make it right! I would push hard.....

[@loves2shoot]

@@TranTek I bought ridgid because of LSA (lifetime service agreement). Hope you registered them at time of purchase? If not, I'd petition them, and try to collect any proof of purchase (even if it is cell phone pics or friends testimonials?) Good luck!

[@TranTek]

loves2shoot i had moved on to Bosch and love it, it lasts long long time. i also added Milwaukee to step up for bigger torque 1/2

[@timshao9139]

Thank you for that very detailed, educational, well layed out video. I watched it from beginning to end, with not much waste of time like other videos. You fast forward over the monotonous parts and did not waste my time. I'm sure that video took way longer than 57 minutes to make congratulations. I really look forward to talking apart my batteries in the future, if there are any problems in the likes that ego will send me a new one. I love the setup, very nice kit you got there brother. I would love to have a fluke and o scope in the future. I have a little experience with electronics and would like to know more. Thank you. I look forward to the next video.

[@reinikesretro]

Your videos are impressive! Very detailed and worth the watch! I have 2 batteries, one a 7.5Ah and a 2.0Ah I'm playing with. The 2.0Ah one had the continuous blinking green light and wouldn't take a charge. By now it is completely dead and need to figure out how to "jump" the cells so it'll charge after repair. The 7.5Ah wouldn't charge at all. It had juice when I bought it. Anyway, thanks to your videos, I'm hoping to resurrect them. Hopefully the 7.5Ah more than the 2.0Ah LOL!

[@ThriftyToolShed]

I totally understand, hopefully you will get them up and running. The cells being completely dead is not good, most likely have lost capacity on some cells! Best of luck to you! Thanks for your comment!

[@davidg5991]

Thanks for your excellent video. One of my batteries has just started doing this - unfortunately it's out of warranty. I'll get another Q12 and give it a go.

[@bahriyroman407]

Hi. You are doing a good job!!! Please help me find that MINI Transformer which is located between the 25v 47uF capacitors. I will be very grateful for your help

[@michaelbirchall2247]

Great work, I've just fixed my battery with this info. Thank you so much.

[@ThriftyToolShed]

Awesome job! Glad it helped and Thanks for your comment!

[@bappel7577]

Thank you so much for your videos. You're able demonstrate / teach technical information in a non-technical manner. That is a real gift and so happy to have found your channel. One question..Have you thought about digging into the Ryobi 40V batteries? I have several which need your technical skills.

[@ThriftyToolShed]

B Appel, I have had lots of trouble with the ryobi 40v, all mine had issues with bad cells and I have replaced some cells but they seemed so problematic that I am running my only 40v tool by using 2 18v ( Makita or Milwaukee) in series and it runs it fine, but not pretty! Lol!

[@ThriftyToolShed]

B Appel, Thank you for your comment!

[@ThriftyToolShed]

hello_world, I have not.I have only reused tested good cells from other packs with bad cells at this time. It would be great if someone has found this available for sure. Thanks for your comment.

[@soberthinking2102]

Since you have so much experience with these EGO Battery Packs, I would like to ask your advice on a problem with an EGO Battery Pack that the manual does not address. I have a new EGO 56V 2.5AH Battery Pack, bought two months ago with an EGO lawn trimmer. After the trimming was done on the lawn (September 20, 2022), I fully charged it and set it aside. So far, so good. The EGO Battery manual says that it is supposed to go to 30% after a month in storage, but as of November 5 , 2022 (well over a month), it still shows all 5 lines of FULL charge. It appears the BMS is not working to lower the battery pack to 30%. Is this battery defective? I read that at 80% or more charge, Lithium batteries lose 20% per year of capacity. I don't want to lose 20% a year. Just running the Battery Pack on the trimmer to force it down to 30% is NOT what the manual says I am supposed to do. What should I do?

[@futurecolemaniii5191]

Man, you are good...I learned so much from this video that you produce concerning the Ego battery...I have two Ego Lawnmowers and six batteries along with the blower...Recently; I just had 4.0 battery go down on me and it is flashing red when I press the button and I think I am having the exact same problem as you... Where did you get the specification diagram from and where do you order the parts? Any help would be greatly appreciated because I am trying to save $225.00 dollars for a new battery plus I would like to learn how to fix this wonderful battery... Thanks in advance

[@ThriftyToolShed]

Larry Coleman, I understand trying to save money by fixing it for sure. I do not own the 4.0 pack but they are most likely similar. When you ask about the diagram, what are you asking? I do not have a actual BMS schematic diagram. It would be awesome to have one, EGO is not going to let that get out! What I did was went through and checked all components I could by finding the identifying numbers and searching online. Years ago you had to search Digi-key, Newark, or Mouser etc. for parts but now you can just google it and you can find 80-90% of data sheets that easy. Same way with ordering components. I used to have to order from Digikey, Newark, etc. but now you can find common parts on Ebay etc. without a minimum order number. Not always the way I do it but some parts from big Electronics suppliers are only available in the 1000’s And that sucks when you only need 1 or 2. Best of luck to you. Hope this helps.

[@ThriftyToolShed]

Larry Coleman , btw I should have mentioned that in my first video of the look inside the battery I mentioned how well EGO did on my battery so if it’s still under warranty that are really helpful and will typically let you keep the battery to recycle : )

[@leochen4891]

This is hardcore trouble shooting. Great job.

[@ThriftyToolShed]

Thanks for your comment!

[@Sdelgado0267]

Great work, thank you for sharing.

[@Chris-e5f9z]

Great video, thanks for the help.

[@ThriftyToolShed]

Glad you found it helpful! Thanks for your kind comment!

[@ericrieker6704]

Do you accept boards sent to you? I have a 5.0ah battery that may have gotten rained on while in a blower. It has full voltage and will only operate any tool for about 3-5 seconds before it cuts out. I have it apart and would love to get this battery fixed to have another battery in my arsenal. Any help is appreciated. Great videos btw!!

[@ThriftyToolShed]

Thanks for your comment! I wish I had time, I do get asked this often. I work full time+ and try to have time to edit videos to post. I try to help by posting what I have found with a similar items and do try to help if someone is having issues.

[@superiorraingutters]

Love your video, it's extremely detailed. My battery stays blinking green non-stop. Is that controlled by the chip you were proving on with the red blinking light?

[@ThriftyToolShed]

Yes that shorted transistor did cause it, just make sure you are more vigilant in keeping the battery from discharging to far until it is repaired! I think I mentioned in the video that it will pull all the cells down to zero if not watched closely due to that transistor being shorted! Best of luck and thanks for your comment!

[@Saturn49YT]

DBG is usually short for debug and is likely an output from one or both of the microcontrollers. It's sometimes used as an extra output pin that can be used to debug the firmware on the microcontrollers. Though it really could be anything related to debugging.

[@ThriftyToolShed]

True! It might be indeed.

[@johnt7059]

Thanks so much for this video, what a great help it is for diagnosing EGO battery issues. I have a new 5.0 Ah EGO battery with a bad component on the board (no 3.3 volts anywhere) and I was wondering if you knew if a BMS board from a 2.5Ah battery would be interchangeable with the board on the 5.0Ah battery? There seem to be a lot of used 2.5Ah batteries for sale online, but I can't seem to find a 5.0 Ah. If the boards are the same, it seems that I could harvest one from a dead 2.5Ah battery to use in my 5.0Ah. Thanks so much for your videos!

[@ThriftyToolShed]

John T , Hi, sorry I do not know anything for sure about the 5.0 or 7.5ah battery. I would be quite sure they are different. When you compare the board you have to the 2.5ah in my video do they look different?

[@ThriftyToolShed]

John T, Thank you for your comment!

[@dfontaine5488]

Thank you for the video. I have a pack that shows fully charged with a green light on the charger and green solid light on the battery when pressed, however my blower would shut down after a few seconds. My cells all measured 3.25V but I have now charged to 3.8V. The tool seems to work properly now but the battery still will not charge on the charger. Any ideas what my problem would be?

[@ThriftyToolShed]

If your pack has good voltage level and shuts down after about 10 secs that is a sign that most likely the pack and tool is not communicating with each other through the D-terminal. I have a video discussing the D-terminal a little but I still don't understand it fully. Could likely either be a connection issue with the terminal or either one of the boards not working properly.

[@dfontaine5488]

@@ThriftyToolShed The problem is that the pack shows fully charged when the voltage was too low to operate the tool. Just curious if you have an idea what might cause that type of error.

[@ThriftyToolShed]

@@dfontaine5488 Ok, so once charged it runs the tool fine. It could be that one or more cell is going/dropping below around 2.8V or so and that will shut the pack down even of most cells still have some charge in them. This is a common issue when one of the cells in series loses some capacity and the pack shuts down prematurely. The difference here is that it usually will flash red before shutting down though. That's odd. If you test all the cells and you do not find one or more lower than the rest then in that case it could be that the BMS board just thinks it's low either due to corrosion on the connectors to the BMS board or a fault in the BMS itself. I have a EGO pack repair video showing an issue with corrosion on either a 4 ah or 5 ah pack. Best of luck to ya!

[@marshsees1532]

Awesome video! Thank you, I learned a lot.

[@sylvainlathuy2702]

Thank You for this video! I am having similar issues on a 6Ah battery and followed your troubleshooting... Q12 is faulty indeed! Then on the other side of the board R171, R192, R210, are visibly roasted so I will replace them as well. I tell you if it works afterwards. Cells went down close to 0v but I could recover most of them but I expect their capacity to have dropped.

[@ThriftyToolShed]

That is good to know. I have a 5.0Ah on the bench right now and for the first time see that the BMS board looks the same as the 2.5Ah. I have been wondering if that was so, I have not had a failed one til now. Hopefully your pack will be fine, I usually find the cells are just as you stated lower in capacity even if you save them! That's the really bad thing about this failure, if you keep it charged it will protect the cells but it's a chore and most of them do eventually get pulled to zero before we get around to disassembly and disconnecting the BMS. Best of luck and thanks for your comment!

[@sylvainlathuy2702]

@@ThriftyToolShed I finally found time and all necessary components to repair it and... It works! Thank you again for this useful troubleshooting. I replaced all cells by 3Ah capacity so I got a 9Ah pack :) I had to replace a temperature sensor that was torn off during the un-mounting as well (J3Y) :/

[@ThriftyToolShed]

@@sylvainlathuy2702 That's awesome, excellent work!

[@leslarson2642]

@@ThriftyToolShed When replacing cells in the battery packs, what Current factor (C) is needed?

[@ThriftyToolShed]

It is hard to say for sure which cells are in the packs due to the unmarked cells but we know they are close to 2500mah due to the 2.5ah, 5ah etc. rating. I bought several bad packs from eBay over the last 4 years or so and tested and collected the good cells from some packs while that helped me repair many packs. We know they will be high current cells. We have had some comments from viewers on here saying the cells they thought their packs have..... (Jonathan Ridder) mentioned his had Sanyo UR18650NSX. (Ipissed) mentioned his are Samsung INR18650 with phase change sleeves made of paraffin wax/carbon graphite. I keep lots of spare cells from almost new packs parted out as well as other cells tested very well for capacity. I usually do not recommend cells because of some fakes out there The main thing to make sure is that the seller is truly selling genuine cells. I have had great luck using 18650batteeystore.com in the past. I share some of this in this video if you find it helpful. kzbin.info/www/bejne/nGq2gIOMetaaodk

[@xxycom8963]

@Thrifty Tool Shed. Binge watched both your videos, repairing eGo battery pack. 👍👍👍👍👍. Enjoyed it very much. Thank you. You and your patience of brute force trouble shooting when schematics are not available! Most of us don’t have that patience, though in my days, I have reverse engineered TTL boards. I stopped after large scale ICs appeared. By the way I was looking for tear down of eGo self powered (2102SP) mower, and your videos appeared. My 2102SP is stuck on high speed self propel mode. Seems many users face the same problem. Let us hope you tear down the Self Propelled, and analyze the logic boards, some day.

[@ThriftyToolShed]

Thanks for your comments. I only have a non-self propelled EGO mower but that is very interesting for sure. I have not heard of that being an issue with those. Is it all the time once it's turned on (activated)?

[@xxycom8963]

That was a fast response.Wow! No it is all the time. There is a speed controller in the handle. I opened it it. It is a 2.2k potentiometer, and measures properly. This pot probably goes to a small logic board, which maybe a pwm controlling the field current to the small motor which turns the front wheels. The design is a nice design, eliminating any belts. Letting the large electric motor do the lawn mowing, and the small one do self propulsion. As to your question whether it is a general problem, I think it is, judging by the complaints in eGo Community Forum. The users are complaining about nonfunctional, to stuck on high (my case), or stuck on low self propelled speed. Service times by eGo being the way they are, 6 weeks, I have not bothered sending it in mowing season.

[@ThriftyToolShed]

@@xxycom8963, Ok so several different issues, I do wonder how close this controller is to the chain saw brushless motor. I did repair a controller for the 14" chainsaw and it had shorted power mosfets. I bet it is a close design maybe not the hall effect feedback though!

[@xxycom8963]

Thrifty Tool Shed , thank you for your response. If you can control the speed of the chain saw (say, where a pot sets the operating speed), then it is possible that the designs maybe similar. But if the chain saw speed is not controllable, then the designs are different.

[@ThriftyToolShed]

@@xxycom8963 , Yes, I thought about it after my last reply, it is most likely more similar to the blower speed control which does have a speed control on it as the chainsaw does not. I repaired the saw in a video, but the Blower ended up being a fault finding video. I did find issues, but in the end stopped due to the repair cost being too great, but it may be helpful to you if similar? The mosfets are similar to the saw Controller board. And also had shorted smd mosfets but also seemed to have a bad IC chip. So cost of fuses, mosfets and main IC chip made mine not cost effective. I hope mine was the exception rather than the rule, and that others had more luck! kzbin.info/www/bejne/jKDdd5J_fpVjY9E

[@jeremygilroy5593]

Your video are awesome. Dop you have a pic of each of the connectors? When removing the top off my 4aH, the the wires pulled from the top (single ) connector and I do not how it goes back. Also you are ablew to remove the potting material from the board, mine is black and does not come off as cleanly at all. Any tips?

[@ThriftyToolShed]

Thanks for your kind comment! I do have the video in the link below that shows the 2.5ah BMS wiring that was requested some time ago. Hope you find it helpful. The 4ah may have a few more wires, but they are extremely similar. The potting on all mine so far has not been that bad so I don't know why yours is different. All mine were dark grey silicone potting. Strange how some are different. I have not worked on any of the newer 3rd Gen with the segmented fuel gauge yet to say how they are either. Best of luck to ya! kzbin.info/www/bejne/iJe3e4J6pM1rh5Y

[@jamesdrews751]

I've been giving troubleshooting a lot of thought. Would it help to take a good BMS that is healthy and plugged up. Take and record all the voltage readings from every component. Then use this as reference material on a bad BMS to help pin point the issue? I realize different functions have to be considered. Your thoughts? Also, have you found a good source for parts? We need a place where we can just replace the BMS board on the cheap. I'm looking and searching. If I find a resource for parts, I will let you know.

[@ThriftyToolShed]

Yes, that is absolutely a good way to troubleshoot and find out more about a board especially when we have so little information on it. I will do resistance checks/diode checks on board powered off and compare at times and I have from time to time done exactly as you mention with a known good one powered on and document/compare. You may know this, but ASA or analog signature analysis is a major player in board repair especially in big industrial board repair shops. Using a Curve Tracer you can compare analog signatures between two boards and see the differences from point to point. It's really neat but very time consuming so it's mainly helpful when many of the same boards are repaired often. On the BMS board I have tried hard to find replacements. I even have one video I shared on the 3rd party battery for the 56V EGO pack and since it was sent in for me to review I was amazed at how well the BMS was copied ( basically cloned) so I contacted them trying to get them to offer us parts in particular the BMS and the manufacturer said they would not sell individually at this time. I keep hoping to get my hands on some. I even offered to order a large lot (thinking or hoping I would have no issues with people wanting them so my money would hopefully not get tied up), but still they were not interested in selling the boards. Yes, we need to find a good supplier of these.

[@andrewsnider7331]

Replaced Q12 & fixed the blinking green LED. Thanks for the info. Reminds me why I don't solder much....!@#$#@#$%

[@ThriftyToolShed]

Excellent work. The SMD devices can be a challenge for sure! Glad it worked and thanks for sharing.

[@abuzar1]

Does the battery discharge itself just by using energy to power the blinking LEDs? So if I were to remove the LED would it have the same result as stopping the source of the discharge? Continue to use battery like normal after that?

[@ThriftyToolShed]

Well, it would perhaps slow it down alot, however, the DC-DC Converter will still be on and will draw some current. I have not tested this to say for sure though. Replacing Q12 shorted transistor will usually get the pack back going.

[@abuzar1]

Thrifty Tool Shed Yeah it’s better to do the job correctly. The removing the LED was my thought before I knew of the exact problem. Thank you for the video you helped a lot!

[@johnnymurphy6593]

The manual states that after 30 days the battery discharges itself to the 30% storage level. This is a BMS function - the BMS has a clock/calendar chip, probably to trigger this activity. The manufacturer recommends fully charging the pack before storage, and storing them and the charger in a dry temperate environment such as the house. Some people report their packs don't seem to self discharge. Lithium batteries last best when stored in the 30-50% charge state region. The automatic self discharge takes some time to complete, warms the end of the pack with the LED, and the LED blinks green during this process according to the battery manual troubleshooting chart.

[@ThriftyToolShed]

Correct. As I stated in the video that would be normal. The video shows what thousands have now seen when what I found as Q12 shorted it will not stop and Drain To ZERO! It is now over 3 years later and thus is a known failure of the EGO pack. Please watch video for more information, after all it is free!

[@fishinman69]

Hi there. Awesome job! I have a problem. I want to use a diff battery to power my ego blower but it would only stay on for 4 seconds. It has something to do with the D connection. How do I bypass that?

[@ThriftyToolShed]

The short answer is I don't know. I still am not sure of what all the D terminal does. I know it reads around 10k ohms at ambient thru the NTC (on the BMS board) back to Negative terminal and it also has a pulse or signal from battery management board which let's the tool know when to shut down. I notice also the fuel gauge LED lights up when you start the tool so I believe it is i2c or maybe can bus communication between the pack and the tool? I looked into it enough to know it has what seems to be 2 different 15khz pulses at around 18 microseconds separation!

[@fishinman69]

@@ThriftyToolShed when I connect my 60v snapper battery on the ego blower connecting the D(from the ego) to the ohm on the snapper battery, the led fuel gauge would turn on as I run the ego blower but would turn off after 4 seconds runtime. I can get 4 sec bursts only after I let go of the trigger for a sec. And I tell you what the blower is much more powerful at 60v than 56v. Felt like turbo was on without the turbo button.

[@ThriftyToolShed]

@@fishinman69 It's interesting that it only last 4 secs! I do remember testing my blower a while back and with the white wire (D) unhooked (basically just jumping + to + and - to -) my blower runs 10secs then shuts down after not receiving the battery info. Alot of packs and tool systems just use a NTC so it is a ohm or resistance reading between usually the negative and the feed back terminal like D (not sure a out the 60V you have) This EGO system has had me scratching my head! Lol! I have tried to figure it out several months ago to help answer a viewers question about adding cells to increase capacity for the Nexus power system. I did not come up with a solution. Then the viewer decided to add the cells in capacity across the pack in parallel and the pack still registered the EGO pack so it works and increases capacity. So I really have not spent much time on it after that. Especially since it seems like a communication link between pack and tool!

[@ThriftyToolShed]

@@fishinman69 Have you tried it with the pack run down to around 58v by chance? Just wondering if the blower is picking up over 60v as possible overvoltage and shutting down, just wondering since it shuts down in 4 secs instead of 10 if it's protection mode?

[@fishinman69]

@@ThriftyToolShedI thought the same way too but it shuts down the same when I hook up the ego battery without the D connection lol. Thanks for your replys!!!

[@Stikfigs]

This video has been amazingly helpful in my troubleshooting! I have been really enjoying your repair videos, particularly the ones with the EGO batteries. I have a 7.5AH 2nd gen that seems to have died on me while using it in the leaf blower for snow.. I seem to have found an issue with the U5 microcontroller "95F012K" chip on the BMS.. I was wondering if you have any spare 7.5ah BMS boards that I can purchase from you so I can salvage that chip from? Thanks for hearing me out!

[@ThriftyToolShed]

Sorry. I do not have any 7.5ah packs at all. I have not worked on one yet, so unsure if a difference in 5ah and 7.5ah BMS board for sure. Thanks so much for your comment and best of luck to ya!

[@jeffstumpf9449]

Wonderful video well explained

[@ridemfast7625]

Great video, thank you for taking the time! Tested what I could and of course Q12 is shorted. But, the two photo couplers did not test like yours. The transistor side had impendence in both directions on both couplers. They both measured the same on all pin outs. Not sure if its me and the vom or coupler. The bats checked from 4.02 volts to 4.41 volts. The electronics is far too small for my soldering setup and skills. Fun to investigate and learn though. Brings back High School electronics from the 70's. lol Anyway, any ideas on what to do with batteries.

[@ThriftyToolShed]

Hi, Thanks for your kind comment! The Q12 is not very hard to replace, the bottom right pin or gate pin is the toughest becaue the trace and pad is very tiny if you decide to try it just be very careful on that pad especially. Are you asking what to do with cells as in what you can do with them or how to recycle them? You can use the individual cells for many things including flashlights etc. that you can purchase really cheap and can run for a long time from individual 18650 cells. You may have to take the phase change sleeve off the cells for some uses. As far as recycling you can take them to a Lowe's or Home Depot and put them in recycle bin or if you feel like dealing with it, these EGO packs still bring pretty good money on eBay as non-working for parts only. I still see 2.5ah packs at times bringing over $25 and 5ah packs over $45. Hope it helps...

[@jayesluton]

Hello, I thoroughly enjoy your video's, clearly you know a fair amount stuff on these batteries. I was wondering do you repair viewers batteries?

[@tripjet999]

"video's"...what?

[@ThriftyToolShed]

What?

[@adamcopple7131]

Excellent video, watching from the UK. This is a little beyond my skill set. Anyone else watching from UK? Do you feel confident to check and repair a 10Ah battery for me?

[@Payaso_M13]

Great job! How do you know the part number of the transistors to find the datasheet just by looking at? Great videos by the way.

[@ThriftyToolShed]

They have the part number laser etched on the chip. And just a few minutes search usually yields the data sheet. Just like the transistor MJD117 for example. Sometimes the chips are custom and can not be found. I found no custom chips on this one, I found pretty much all of them.

[@Payaso_M13]

@@ThriftyToolShed awsome thank's very much. I guess I'm spoiled at work where the part manufacturer on the BIlling of Materials and just mouser for the datasheet. I'm starting to do repairs at home on old retro stuff. so I was curious on it finding parts. Thank you very much your videos are very addictive to watch !

[@ThriftyToolShed]

@@Payaso_M13 Thanks for your comment. Yes the BOM and schematics are heavenly, unfortunately they seem to be a thing of the past for consumer electronics, I miss that alot. We have to go into it blind...

[@tjncooke]

I've been looking at EGO tools and wanted to know more about the BMS. This was a great deep-dive into just that! It's the first video I've seen where someone goes under the potting material! It was heartening to see that it was relatively easy to get in there; I was initially thinking the potting was the hard material which would be next to impossible to get off. I am still interested in what comes out of the D and T pins, since the tools must receive a data signal from the battery telling them when they're dead or over-temperature. I've seen some tool tear-downs and the T pin doesn't seem to be connected, so that's probably just used to communicate with the charger. But are these bi-directional, or just output from the battery? Anyway, my musings aside, great video!

[@ThriftyToolShed]

tjncooke , Very good question indeed, maybe we can figure that out soon! Thanks so much for your comments!

[@pashko90]

@@ThriftyToolShed Did you have a chance to play around a data protocol on this packs?

[@ThriftyToolShed]

@@pashko90, I have a video on "What's the D-terminal?" Where I shared some of things I have learned, what I guess maybe happening and then mentioning that we need some help here going further into it. I don't have equipment yet to test for protocols, but seems it is using one for sure. I still hope some Electronics Engineer with BMS circuit design background will come across the video and decide to pick up on it and share some knowledge. Until then we have much still to learn!

[@pashko90]

@@ThriftyToolShed yep, i checked it out already, i'm workig with CAN bus more, lets see if i will have some time to figure it out.

[@rickc4336]

Question at the end of this....my whole lawnmower went in the lake (don't ask). After taking it and the battery apart to dry, I was able to do a full mow, and the battery still reads 51-52v, so I figure the batteries are OK. However, it won't charge and I get the fast blinking green light, similar to you. As you and another said the Q12 is a common culprit, I went straight to the Q12 to test it. I have not tested any other component yet. The results of the Q12 tests are as follows... Test 1: black lead on Base, red lead on Collector = 0 volts (yours was 0.67v). When I reverse my leads I still get 0v. Test 2: black lead on Emitter, red lead on Collector = 0.551v (yours was .002). When I reverse my leads I get 0v. Test 3: black lead on Emitter, red lead on Base = 0.685v (your leads were reversed from mine, and you got 0.671v. I get 0v when I reverse my leads to match yours) Would you agree, especially due to Test 1 = 0v, that Q12 is faulty ? And any comment about Test3, where I only got a reading when my leads were reversed from yours ? Thanks, Rick

[@ThriftyToolShed]

Hi Rick, I would say from your findings that Q12 is surely bad. And its been quite some time but yes the 3rd test seems off also. I believe it should be around .6V the way I had my leads and open when reverse like you had yours? Best of luck to ya!

[@rickc4336]

Thanks for your feedback - I appreciate that.

[@No0bZiLLa420]

howdy. first i would like to thank you for the very in depth diagnosis you did. it has helped me atleast dive in and remove the silicone protector from the board. The battery in question is a BA4200 7.5ah and i have absolutely no status indicator at all. when i press it, it doesnt light up or flash. when i put it on the charger the led indicator on the battery doesnt light up or flash. it seems there is no power at all getting to the led and i was hoping if you could tell me what components i should look for to test to see if they are bad. i tested q8, q10, q11, q12 and all seemed to be ok though when checking q8 q10 q11, when i swapped the leads around, it showed resistance on the center pin but only after a few hundred milliseconds (approx). when the probes are switched around, it all checks out as normal i think. but all three exhibit the sme behavior so i chalked them up to good as well. if there is any way you could give me a few ideas man i sure would appreciate it.

[@ThriftyToolShed]

I have not worked on the 7.5ah so I am not 100% sure how similar to the 2.5 and 5.0 packs. I would think the BMS is very similar. The caps on BMS board should have around 10VDC on them as the power rail from the DC-DC converter circuit. This powers up when the push button is pressed. So check that and make sure that part is good and troubleshoot from there. I do not have a schematic of this board so I just probe around and do my best. It's been over a year since I worked on one of these but also check the fuse on the terminal board. I have had these blow, but I believe the BMS is still powered even when the fuse to the output terminal is blown. I wish I could help more. I do have a few videos on some 5ah packs including the blown fuse repair. I basically have shared most of what I have learned about them so far. I also have a video about "What is the D-terminal?" and I mention the BMS a little that I have learned about it and much still left to discover. Hope it helps. Best of luck to ya!

[@No0bZiLLa420]

@@ThriftyToolShed thanks man. I appreciate it.

[@bobgoudie3434]

Hi! Thanks for doing these. They are a big help. One suggestion I might have is looking at the issues/problems with these batteries based on the symptoms that one might see from the battery what a person might look at to fix the problem. For instance my battery is blinking green and this video you showed that the one you were working on was doing the same. For that you replaced the Q12 (MJD117). Unfortunately that doesn't seem to have fixed my board but I'll keep looking.

[@ThriftyToolShed]

Thanks for your suggestion. I can only say I started this journey over 4 years ago to help the community as we learn to work on these together and share what we learn as we learn, not sharing as anyone with schematics or any other information nor claim to have any certain EGO expertise. We are simply creating our own information. Of course 4 years later I wish I could change some things in the video, but with KZbin it is not possible to edit any uploaded video of course. It's either delete it or not. Glad you found it helpful and I have many more as we learn together over the years including repair of blowers, chainsaws etc. and packs with other issues. I was simply troubleshooting the blinking green issue on this video that 90% of these packs have while blinking green constantly without one clue if it was even possible. This is not to be confused with the blinking green for maintenance mode. This is blinking green all the time even while in use and even while charging and the pack will pull down to zero volts if allowed while Q12 is shorted. Thanks for your comment!

[@raymiller5738]

Thanks so much, I've now had 7.5AH packs for the same issue, EGO has been great under warranty but their does seem to be a problem with the Q12 either a bad batch as you say or design problem. I'm trying to work out the failure mode? any ideas?

[@ThriftyToolShed]

Hi, Thanks for your comment. I guess I am not sure what you are asking about the failure mode. Are you having a different type of failure with the 7.5 AH?

[@raymiller5738]

Are the circuit conditions exceed the transistor's voltage, current or Safe Operating Area (SOA) specifications? Or of course, it could be the whole batch of transistors from a particular manufacturer. I suspect that failure occurs when the battery packs either overload or enter the low state of charge cutout condition. While my batteries are all 7.5 Ah, it is happening to small packs as well as you have found. The transistor SOA at 50Volts is only 0.3A, I was trying to find a replacement in the same case with a more generous current at 50V but this proved difficult. When I get the new transistors in I'll have a look at the voltage and current on my CRO also to see if any voltage spikes are occurring. I'm really surprised that the BMS board is not changed as this is all it needs to effect a successful repair. I really appreciated the video it helped me save heaps of time. @@ThriftyToolShed

[@ThriftyToolShed]

@@raymiller5738, Very true I have wondered the same and had issues finding same package in higher ratings so I still just use the exact match as I did in the first one I repaired. I have not had a failed transistor yet out of the repaired packs so it could possibly be a bad batch? Although I have suspected as you mentioned that in certain conditions the ratings could be getting exceeded, but have never caught that being the case. Thanks for your comment and I wish you the best on your repairs!

[@markcreighton1100]

The MJD127 is a DPAK 369C and is rated at 8.0A so that it is the same footprint as the MJD117. I purchase a few of these in case the replacement MJD117's failed.

[@ThriftyToolShed]

@@markcreighton1100, I was going to do the same. I have not had another failure since so hopefully just a bad batch! Time will tell...

[@andrewche9803]

Great job!!! I have a same battery that have some problem. I checked it and find 5 cells were died. I replace them it's ok, but I have a problem, there are 13 wires connect to each cell, I reconnect to 12 of them after repaired, but the 13th one I don't know where to go. this cable is black color and nearby Q31. in J2. Would you mind help me find out this information? thanks a lot.

[@ThriftyToolShed]

I do have a video on the EGO 2.5ah BMS wiring that I uploaded to help someone with a similar issue. Let me know if it does not help you, and I can look further into it. Thanks for your comment! Best of luck to ya!

[@shckltnebay]

Thanks for the vid, mine is blinking green, does it mean its bad or just doing that discharge cycle, was working great but i was only useing about once a month or less

[@ThriftyToolShed]

Well if it keeps on blinking even after you charge it up then it is bad. It will keep pulling the cells down to zero and ruin the cells if you do not keep it charged well and often. If working properly it will not pull below 35v for sure and it would of course reset once it goes through a charge cycle.

[@shckltnebay]

​@@ThriftyToolShed Just tested it at 54 volts, got the part coming but man that epoxy looks really hard on mine

[@shckltnebay]

@@ThriftyToolShed Ok got the board out and removed the PNP Transistor, im getting a short on the right leg to the top pin

[@ThriftyToolShed]

@@shckltnebay Mine was a gray silicone based material, they may have changed it?

[@ThriftyToolShed]

Hopefully that will take care of yours as well. Do be careful with the right or pin 3 desoldering, the Trace is easy to pull up. On mine I will carefully desolder the smaller pin1 and pin 3 and gently lift up off the pads, then remove the whole thing since the base is such a large area.

[@Adidan64]

Excellent work! I have the green blinking as well, EGO support treats this as a known problem and is sending replacement. Wonder if they couldn't just be refurbishing these with new boards, I'd imagine bulk of the cost is in the cells themselves?

[@robertstewart2518]

My 7.5ah just did this, and theybare replacing it under warranty, but Im wondering why they dont just send me a new top half and say plug and play. The batteries are good but useless with out the board.

[@wlin98004]

Where do you get the circuit board holder? It is very handy.

[@ThriftyToolShed]

Hi, The holder is from ebay but I did add the flexible arms myself. I added link to both below if interested. I just drilled two holes and mounted the flexible hoses to the base as a helping hand. Hope it helps. Thanks for your comment, It makes me think others may want to see what it is also, perhaps quick future video? Board Holder: rover.ebay.com/rover/1/711-53200-19255-0/1?icep_id=114&ipn=icep&toolid=20004&campid=5338325412&mpre=https%3A%2F%2Fwww.ebay.com%2Fitm%2FCircuit-Board-Holder-Adjustable-Vise-Electronics-Repair-Clamp-Soldering-Stand%2F333213540273%3Fepid%3D710122992%26_trkparms%3Dispr%253D1%26hash%3Ditem4d95131fb1%3Ag%3AuAUAAOSw95lc7I1f%26enc%3DAQADAAAB4KX%252FKt4E1xf3SDqEdBclaYZuZzce1i%252F95Xd0z7gDWX%252FJBSonIj91o%252FfiMvEuX5vNIqdXrgRGQU%252BaaCeZuymqN3iFZmvfv2yVm1qChZOczBGaa%252FVAxZR%252FY98wiyGaR%252FIxXykHh7C3DU2pkd6NF5PdPIA%252F7nPckpUd2d9BXvtlD4ho%252F%252BHpocf7v0oZSHNWZHZt3UHB5PGVJI4P6Dv8D4F%252BYSpzRj76sQQmkmi698Ym8tFkWJ%252BYqJsDFKnLKGpZ%252F5359L0SAp%252BxbL%252FNJUcgrrD9tXV3XJ%252FJb80hmjR4Vv%252FAPiO1ENBhfd62Dqu6SNGdFSF0rR6H2JhFFVqIejyY%252Bv95KSiLBmh%252FPsSpYFTBAacd6J0f5NQoPiNQsTShf08qRaBestYkh8ejh%252F5AwtQysCO7MR2j3eidiGcyH%252BrBhTy4Na77SYIb5tG4PZJajZBuVyvg93tACCBk3CicRwCq7Hvnl7MUAtAtXDXwjl2aZ2VrOKcsBXu3wn66jel%252BBOn%252BXL3jCB83EQI15QLzVJMWsrnGWEltAuUmw2sWf4K5MGrxSPY9Q0xWwVHKVnC65tzYF8JWzPsxOv8gII4F7dCDne3rkszi8l7az6aDhawzHTzaIHw2nmKVe4Cc%252B%252BZdS4yM4fyvvA%253D%253D%26checksum%3D333213540273e6f94d3b25b84a0ca552c9370d8dcc28%20 Flexible Coolant hose:rover.ebay.com/rover/1/711-53200-19255-0/1?icep_id=114&ipn=icep&toolid=20004&campid=5338325412&mpre=https%3A%2F%2Fwww.ebay.com%2Fitm%2F10-Pcs-Round-Nozzle-1-4PT-Flexible-Oil-Coolant-Pipe-Hose-Blue-Orange%2F282610160803%3F_trkparms%3Daid%253D555018%2526algo%253DPL.SIM%2526ao%253D1%2526asc%253D20131003132420%2526meid%253D174705743b8f45c096be36f2866b8394%2526pid%253D100005%2526rk%253D5%2526rkt%253D12%2526mehot%253Dpp%2526sd%253D163003388384%2526itm%253D282610160803%26_trksid%3Dp2047675.c100005.m1851%20

[@xxycom8963]

Thrifty Tool Shed use bitly, to shorten these monstrously long urls

[@user-kx4dj5ee3o]

I have a good pack and bad board. Is there a way to run the ego equipment without the board? Mine will run the equipment about 5 sec then shut off. I have a charger so, charging the battery is not an issue.

[@ThriftyToolShed]

No the D-terminal is communication between the took and pack. kzbin.info/www/bejne/fl7LmJqLjcyMorc

[@angelgkd]

Fantastic!!! Thank you!!!

[@lynn2207]

Very impressive troubleshooting and component repair. I have a 2.0 Ah battery from 2014 that has quit. It was completely dead on the charger. I opened it then put it back together and now it blinks on the charger and the charger clicks. I will buy a new battery and try to recycle this one. Would it be of any interest to you?

[@ThriftyToolShed]

I would take it, but to be fair, they do bring some money on eBay if you want to try that!

[@lynn2207]

@@ThriftyToolShed I will send it to you if you will cover the shipping.. Lowe's had a $70 delivery charge but some eBay sellers had ~$15 fee, so not sure of cost or any shipping restrictions.

[@ThriftyToolShed]

I don't understand the delivery charge I guess?

[@rachelbinto]

I have a 2.5Ah battery which didn't take charge. I opened it up and saw that that Q12 is shorted but there is also some trace burned near what looks like a voltage regulator. I am going to try and bridge the trace with a piece of wire. But accidentally I must have pried off a component hat is marked "RT2". Will you be able to tell me the value printed on this component? Looks like a resistor, and the "T" in it probably means its used for temperature measurement/biasing.

[@ThriftyToolShed]

rachelbinto, hi I will help all I can. Unfortunately the RT2 is a component that is unmarked. However I believe as you that this is a NTC. Mine reads a value of 14.1k ohms @ 65F ambient while in circuit. It also goes down in resistance with increase in Temperature. Hope this helps.

[@rachelbinto]

Yes that's great help, thanks, In a pinch I can just solder in a resistor and see if it works. I just ordered the Q12 transistor from digikey. Like I was saying the trace is very badly burned with deep charring into the PCB itself. I believe the trace is the output of a diode which is connected to a decoupling cap, which is also input to that large voltage regulator. The output of the regulator is probably connected to that shorted darlington transistor which may have sucked too much current off the trace to have burned it this bad. This is a great video that you have made. How did you know details like the two connectors are feedback from individual cells etc? Do you have schematic or something?

[@ThriftyToolShed]

rachelbinto, I wish I did have schematic. There is no information at all that I know of. I just spent some time troubleshooting and tracing out the best I could but there is still alot I do not know about the bms. I have not seen one yet with the burnt trace as bad as you described, but that smaller trace has lifted off on a couple of mine I have repaired so far. Looks like you are on the right track. Best of luck. Let me know your results. Thanks for your comment.

[@rachelbinto]

So, I have not been able to fix this board yet. I did have a shorted darlington transistor (just like yours), but in addition I also had some traces burned near the T1 transformer and the Q10 transistor to the point I cannot tell how they were originally connected. Will you be able to use a multimeter and tell me what is the 3rd pin (pin closest to the gate of Q10) of the T1 transformer connected to? Also what is pin 1 (gate) of the Q10 fet connected to? Right at this location the traces are gone and I have no idea what connections are missing.

[@ThriftyToolShed]

rachelbinto, it looks like the 3rd pin you are referring to is going to D11 anode which is right next to it and its cathode leads to C3+. It seems the gate of Q10 goes to R51 which is a 20k ohm resistor and that resistor leads to pin 5 of the U4 chip. It seems that the gate also jumps down to R50 which is a 20 ohm resistor that leads to pin6 of U4 chip. U4 is the pwm chip that I did show on the video with the scope signal. (As you may be aware this is a dense multi-layer board and it could be more traces uses vias that go elsewhere but that it the way the layout seems to me) Hope this helps. Best of luck!

[@alstodolski4991]

Without markings, how did you determine what data sheets to acquire? Some parts are so small as to not have markings.

[@ThriftyToolShed]

I only found data sheets for the ones with markings. Mine had markings on most chips.

[@alstodolski4991]

@@ThriftyToolShed and if you could indulge me, did you have any schematics on the control board? Was your troubleshooting just that intuitive?

[@ThriftyToolShed]

No schematics whatsoever. I wish we had some to share. That is the main reason we share as we can as we learn together. I simply had the desire to learn and share as much as possible early on with these EGO boards. I simply took time to research the components as best as possible and started testing based on those components. The more recent repairs have been around the 3rd Gen BMS transformer failures which was shared by many viewers who had the same problem and many had seen the transformer failure before I did. So we share and learn what we can. Our Facebook page "On The Bench" has many contributors sharing pictures or even videos that help the group also. Even a BMS board layout showing traces, pads and vias. I shared this and thanked them for this contribution in a more recent 3rd Gen pack repair video. I Hope you find some of the info helpful!

[@MrCoder101]

Can you use your own DIY 56V (14s) pack to use with the mower? I know I can attach it to +ve and -ve leads on the mower but not sure if not attaching the middle two leads will cause the mower to not start. I don't have a 14S pack in hand otherwise I would test.

[@ThriftyToolShed]

Sorry, I do not have a Mower so I am not sure. I would think very likely at least 3 terminals are used and maybe all 4. Just due to monitoring the temperature if nothing else!

[@2flight]

brute determination. Great video.

[@surferdudemi]

At 37:10 ... TP_3V3 is just a signal name on the schematic where the "V" takes the place of the decimal point, because you often cannot use punctuation when naming signals in PCB design software, or punctuation makes it confusing. But you can add silkscreened labels on a PCB and use whatever text you like, so that's why it says 3.3V above that capacitor.

[@ThriftyToolShed]

It's been 4 years ago for this one. I believe I was simply stating they both are screen printed and may be the same 3.3V rail. I simply meant at this point in sharing information I was not sure if it was the exact same 3.3v rail. I am very aware that sometimes "v" is used as stated, but unsure if another reason it was screen printed differently. Thanks for sharing.

[@annespacedroid]

What type of potting compound can I use. Preferably the same kind, in case I have to work on it again.

[@ThriftyToolShed]

I wish I could say it's as easy to remove as the original. I have used this type here before, but it's not as easy to remove though. It is electronics grade. amzn.to/3INPat3

[@annespacedroid]

@@ThriftyToolShed Thanks for the reply. The link only takes me to the Amazon home page.

[@bobv8041]

Are the boards identical on the batteries? Just wondering if they can be switched out.

[@ThriftyToolShed]

If you mean between the different capacities they are different. The microcontroller at least does has different program for pack ID. Some tools know which pack is installed.

[@bobv8041]

@@ThriftyToolShed Thanks for the quick reply. I have a 5 Ah and 7.5 Ah. One has bad cells and I think the other has a board problem so I wondered if I could just switch the good board to the other battery. I didn't think the Ah mattered as long as the voltage is the same.

[@ThriftyToolShed]

I have not swapped a 5ah and 7.5ah to say for sure. I know the 2.5ah board did function in my 5ah but the middle board for the temperature monitoring was nut functional. So it may work ok, but as far as the tools that know what is connected may indicate wrong. Such as power inverter and I believe the chainsaw allows more output torque based on which pack is connected!

[@rossthefiddler5890]

That was excellent. I don't use Ego products but another 58v system (AEG in Australia otherwise known as Echo in the US) & I'm curious if they use a time base discharge or not, although I can at least check the level meter on the battery but I am also surprised Ego doesn't have that. I'd appreciate your thoughts on that. Thanks.

[@ThriftyToolShed]

Ross the fiddler, I do not have any experience with the echo batteries at all but I have always liked there gas powered products. The ego does have a more unusual approach to me for battery level. The push button /power indicator shows green if over 15% charged? Red if low voltage level and blinks red when nearly depleted and needs to be recharged. It's different but it works. I wonder if it is that way so the all there packs can use the same bms board with it regardless of the amp hour rating but I only own the 2.5ah so I am not sure about that.

[@rossthefiddler5890]

Thanks for taking the time reply anyhow.

[@alexfursa3854]

Hi ,can you tell me what is diode D12 value on charging EGO 56V board?

[@ThriftyToolShed]

I do not. Sorry!

[@billrundell2097]

You sir have a career background in repair electronics. The advanced techniques you used have given you away. For the average person, make sure your warrantee card is sent in. Do you work for EGO or similar company.

[@ThriftyToolShed]

I actually work in Industry. I have always loved electronics and fixing things on the bench it's more of a hobby but I do some industrial electronics repairs from time to time. Thanks for your comment!

[@hobbypower2]

Did ego change the batteries to keep it smaller? When i opened mine there were no sleeves around the cells....it is 7.5ah battery from 2017, that im trying to fix

[@ThriftyToolShed]

I have not worked on a 7.5ah pack, but I have always heard the 3S (7.5ah) packs did not have the sleeves! I am not sure if for size and weight or simply the thermal load distributed accross 3 cells may have been sufeccient without them?

[@hobbypower2]

@@ThriftyToolShed thank you for quick reply ... would it be possible for you to take a look at a short video of the bms and readings i get while testing q10, photocoupler(Q6) and Q12?

[@hobbypower2]

kzbin.info/www/bejne/pHWtg319q7Ojoas here is the video... thank you

[@pkpao8]

I have a 2.5AH battery flashing orange what is the fault thank you

[@ThriftyToolShed]

It is typically a temperature fault. They are really good about replacing under warranty. After that if they allow you to keep the pack. I would check ntc connection first.

[@TBM84]

My battery works in my blower for about 10 seconds and then shuts off. The main terminals read 52v. Where should I start when looking to determine why it's shutting off like that?

[@ThriftyToolShed]

Make sure the connections are good on the pack to the tool. If the D-terminal is not detected it will shut down in about 10 secs. after starting up. Clean connections first and if it isn't that it could be a faulty BMS board in the pack. Double check that it's the pack and not the tool by trying another pack though to verify. The only other thing is if the pack is pulling down too low and blinking red then it could be a bad cell in the pack causing that. Even though the battery pack voltage is high enough, once it starts it could be one cell dripping off and causing the shutdown.

[@dabuhone287]

Not sure if you are going to see this but I was hoping you could post the order of the wires in each connector on the BMS. I was taking mine apart and ended up pulling a few of the pins out of the connector and I am not sure where they go now :/

[@ThriftyToolShed]

I do see it. I also have a video helping someone with a very similar question if it helps. I shared the BMS wiring. Just ask if it is any other questions in particular that it doesn't answer for you! Hope it helps! Best of luck to ya!

[@ThriftyToolShed]

If you search for EGO BMS wiring this should come up by the way! kzbin.info/www/bejne/iJe3e4J6pM1rh5Y

[@dabuhone287]

​@@ThriftyToolShed This is amazing, thank you so much! I was able to find which wires go where for the cells. I did pull some of the wires from 3rd connector and I was able to slow down one of your videos to see the order. It appears to follow the same order it comes from Red, Red, Skip, Skip, Green, Blue, Black, Black. I still need to replace a cell before I can test it but I am pretty sure its right. Again thank you so much for your videos!

[@ThriftyToolShed]

So glad it helped. Awesome job getting yours back together.

[@jlustig83]

How would you go about running the mower off of a big ebike battery of the same voltage 14s?

[@ThriftyToolShed]

I have a video called "What is the D terminal " and I explain a little about how the terminal is communication between the pack and tools. I have not found a way around this without at least having one actual EGO pack connected.

[@bahriyroman407]

Hello. Please help me find that MINI Transformer which is located between the 25v 47uF capacitors. I have 2 batterys dead with bad transformers. I just can't find it. Please help if you can. Thank you

[@ThriftyToolShed]

Sorry, I have been asked this several times. I do not know, I have taken the metal can off and still do not see a part number on the transformer, this could even be a custom part for EGO, not sure. What I did was bought several bad packs of eBay several years ago and now I have some spare component parts that I can't find anywhere. The bad thing is when I first started mentioning buying the bad packs on video, you could get them for around $15-18 each in a lot of 3,5 or so, but not anymore. It is hard to find them at a scrap price, which is about all I am willing to pay because without knowing the shape of the cells, they could all be bad. Wish I knew more, but with no real schematic, detail parts list or part number it is difficult. Wish you the best of luck!

[@fx9750g2]

Hi. What is T1 on this board? Can board work without it and what replacement i need to look for?

[@ThriftyToolShed]

The 3rd gen packs have changed the way this is on the board. I have only worked on one of the 3rd Gen with the segmented fuel gauge and I noticed it is different, but not enough experience to say how different. I have an older video about the T-terminal on the 1st and 2nd gen boards. kzbin.info/www/bejne/mqqvmGicgJaGrrc

[@fx9750g2]

@@ThriftyToolShed i have 3rd gen and also earlier gen(2 types: one have 12 contacts on j5, black j3 and 4 big capacitors(c23, c12, c3, c17) and other type has only 8 contacts on j5, all of them are white(j3, j4, j5), and only 3 big capacitors(c23, c3, c17), c12 become smd type. But i still have no idea what is T1?

[@ThriftyToolShed]

@@fx9750g2 Oh, sorry you're asking about the T1 coils on the BMS board! The little metal can. It is 3 coils in the T1 can. We have discussed that much in the comments over the years. I believe they are used the DC-DC converter circuits.

[@ThriftyToolShed]

I have not found a replacement for these coils yet. I have only had one go bad so far and I had a donor board from other packs I have collected.

[@joshkern9016]

Do you happen to know what the surface mount chip resistors are rated at. I knocked a few off removing the silicone. R117, R3, R11 are the locations on the 5.0 ah battery bms board.

[@ThriftyToolShed]

I have the 1st generation BMS board and it is the following: R3- 392 or 3.9K R11- 204 or 200K R117- 184 or 180K Hope it helps, best of luck to ya!

[@joshkern9016]

@@ThriftyToolShed thank you. Will order these along with q12 an hopefully get the battery back going. Is it true that the 2.5 bms board the same as the 5.0 bms board.

[@ThriftyToolShed]

@@joshkern9016 I know they are similar. Mine have different connectors but that may be more of a board revision than the difference in the 2.5ah and 5ah. I am not sure. I do know mine are slightly different! Those resistor values were the same by the way!

[@joshkern9016]

@@ThriftyToolShed my 2.5 an 5.0 have the same connector on the bms boards. I was able to use the 2.5 board to charge an run my 5.0 with out any issues other than the size difference on the housing itself.

[@ThriftyToolShed]

Great to know, that means mine are different because it is just different versions or revisions. I was thinking that could be the case. Just different gen boards. My 2.5ah are 1st gen. my 5.0ah are gen2.

[@pauls311]

Hi. Do you have partnumber T1 transformer from the board ? Is it possible buy it anywhere ? My is broken (((

[@ThriftyToolShed]

I do not. Sorry but I have not any issue with my transformer yet. Great job troubleshooting and best if luck to you! Anyone else out there had similar issues, or found replacement?

[@BigEHeinz]

Great video! I have the same green blinking light problem. These batteries cost an awful lot to purchase. Would you be interested in repairing any?

[@ThriftyToolShed]

Ed, Thanks for your comment. I did not understand the question, if you are asking me is it worth a repair attempt. I do think so. One thing I show later in a follow up video is that I did have to replace a couple of cells to get the pack back to full capacity. Lesson learned is keep the battery charged well until you can attempt repair. It (the evil blinking green light) will pull the cells too low if not monitored well while just laying around waiting on parts.

[@BigEHeinz]

Would you be interested in repairing mine? I don't have the tools to do it justice. The cost of shipping should not be to much. I also would assume that the problem is the same chip you replaced. We can work out a price? Let me know.

[@ThriftyToolShed]

Ed, I wish I had the time. Best I can do is just try to share what I found if it helps someone. I wish I had more time for videos, but I am very limited. Sorry. Best of luck with the battery.

[@RS-pq3wu]

I’m trying to figure out my 2.5ah battery issue. Battery is at 48v. No lights. No reaction when I hit the button. Charger constantly clicks on and off when battery is added. Any idea how to test T1? It’s the only thing that I’m not sure what to expect for resistance and voltage. The Q12 I have is fine. C26 might be stuck open, but I don’t think that would cause this. I’ve tested nearly every diode and transistor. None of them are out of the ordinary. I tested everything on the D circuit you drew and they all seem fine.

[@ThriftyToolShed]

If you have the voltage at the DC-DC converter then it could be the microcontroller itself. Only a guess from here. I have shared what I have found over the years. Best of luck to ya!

[@RS-pq3wu]

@@ThriftyToolShed Thanks for getting back to me! You saying DC to DC converter got me thinking. It must turn the 56v into 3.3v and 8v. I am 99% sure it’s T1 bad on my board. I think this because I bought two more bad 2.5ah batteries. One had a good board with a cell needing rebalance (now fixed), one with a bad board (lights green, but then has a random flickering orange). Good board T1 measures low resistance across top left and top middle legs, bottom left and bottom middle legs, and top right and bottom right. Makes sense since T1 is just some coils. Both bad boards have opens across one or two of those pairs. The board with no lights had an open where 56v comes in. The board with green then orange flicker was open on the 8v side. Any idea where to buy some T1?

[@ThriftyToolShed]

@@RS-pq3wu Yes the DC-DC converter does reduve the voltage for contol board. I believe on video I shared at one point that around 10V on the capacitor close to the T1. Is common. Then it gets dropped again I believe. But if T1 not working that 10V maybe missing anyway? I have been asked that many times about T1 source and parts in general and commented many times. I have not looked for a source for the T1 transformer. I bought enough bad packs over the course of working on them and sharing what we could learn about them so I would have lots of donor parts. Digi-key or Mouser may have one, I typically use donor parts.

[@michaelreeves6623]

I have a 5 amp ego battery that blinks green but also has the charger making a clicking sound. It is my understanding that the clicking can be caused by the batteries being dead but could the m12 transistor be the problem here thus causing the dead battery and then the clicking sound?

[@ThriftyToolShed]

Yes, Q12 transistor if shorted is causing blinking green led constantly. That will cause the pack to slowly discharge and it can go all the way to zero if not monitored close. I would pull the BMS board off the pack if you can until you can fix the BMS. That way it doesn't keep pulling the cells down. And also yes, the relay clicking sound on the charger is usually the charger trying to safely bump the pack up to see if it is safe to charge because it has detected the voltage is lower than it should be to charge safely. This safe voltage is usually above 42V or so on a 14S pack.

[@michaelreeves6623]

@@ThriftyToolShed I will be ordering the Q12 transistor and hopefully my problem is resolved. Unfortunately the cells have all been drained to dead. I don't have all the electronic tools that you have but I need to charge up the cells so that the charger will finish the job. I noticed that there have been sites that recommend jumping the repaired battery with another ego battery so that the charger will complete the job. Do you think this is ok or do you have another way to bring up the charge in the cells?

[@ThriftyToolShed]

@Michael Reeves I have several videos discussing charging these packs. I strongly suggest not ever jumping a dead or unknown condition pack with another. This can cause so much current to flow that things melt and can be catastrophic. I use the Drok DC-DC converter if you don't have a constant current bench top power supply. kzbin.info/www/bejne/fmHEpKh7btSMr5o

[@michaelreeves6623]

@@ThriftyToolShed This Battery that I am replacing Q12 transistor on has cells that are 100% dead. I have been told that If completely dead they cannot be brought back to life. True? Lastly. my neighbor has a dc power supply that is .5 or 1.5 amp with voltage up to 20V. Will this be sufficient to get these batteries up and running?

[@ThriftyToolShed]

Yes, I have mentioned that on video many times also. Once a pack goes too low it almost never comes back and if it does the capacity is usually shorted tremendously at best. You can take a power supply with constant current set to about .5A to 1A max sure not to exceed 4V per cell either and test to see if cells will respond without heating up and you may get lucky enough for some cells to have some capacity, but the pack will most likely not stay balanced well even if the cells all charge up ok. I have many videos on many brand packs talking about cell testing and I do mention it some on one of my latest videos about Lithium Battery FAQ#1.

[@stzig1934]

Hi, what are the white connectors called? I just need to pins to replace on the wires

[@ThriftyToolShed]

Looks to me like molex connectors, but I have not taken the time to figure out what connector system it is. For example it looks close to the Pico-SPOX connector system, that is where I would start looking and comparing if I needed one. Again, not sure, just saying it is similar..... Hope it helps!

[@ThriftyToolShed]

www.molex.com/molex/products/family/picospox I would check into these and see how close they are, seems really close?

[@gudzev78]

Which cells are in this 21700 or 18650 battery?

[@ThriftyToolShed]

EGO packs have 18650 cells with the phase change sleeves. I think the packs 5Ah and below have the sleeves above 5Ah I don't think they do.

[@georgedavall9449]

This Man is a Guru! Amazing! And his voice reminds me of ‘cotontop’ (who has a chainsaw channel) So much great content here, so I just had to SUBSCRIBE! 👍👍👍✌😊

[@ThriftyToolShed]

Thanks so much for your very kind comment! Now I have to check out cotontop!

[@georgedavall9449]

@@ThriftyToolShed You’re Very Welcome, and thanks for the reply! ‘Cotontop3’ Both of you sound similar, and are very knowledgeable in what you do, IMO. Best!

[@ThriftyToolShed]

I have subscribed to Cotontop3! Thanks!

[@georgedavall9449]

@@ThriftyToolShed That is so cool! I will mention that and hopefully he will respond in kind. Support is what it’s all about!

[@blagojeciric32]

Hi there, don't know if Thrifty or somebody else can help. I have 2 EGO 56V 7.5Ah batteries, cells are good but BMS boards are damaged. One of them has R192 and R210 fried and it is easy to identify the value because it is the same as the remaining 12 resistors, i.e. 100 ohm. I suspect that Q48 and Q60 are bad too, SMD marking is X1VX and I have no idea how to identify them and find a replacement. All my Google searches turned out to be failure. The other BMS board is completely dead, no visible burnt components on both sides and all semiconductors check OK on diode test. Any help, is welcome. Thanks.

[@ThriftyToolShed]

HI, I do not have a 7.5ah pack to say for sure. It seems the resistors are in fact 100 ohms as you stated on my 5ah as well. I also have the X1 SMD transistors as you stated. Mine are X1NA. I believe the X1 is the transistor marking ID and the NA in my case or VX on yours is the date code of the chip. For example if you search X1 SMD transistor you will find some like the AO3401A datasheet and it shows X1 marking and the date code also and of course the lot number on the side as well. The data sheet I pulled is the Alpha & Omega AO3401A P-Channel Enhancement Mode Field Effect Transistor, this is most likely not the exact manufacturer but possibly similar. I would personally check these if i did order some and compare with diode check across known good board if possible. As far as your dead board, it is kinda hard to say without putting eyes and hands on it, but I would check to make sure power from the connector is getting to the board ( the roughly 58V that is) and also make sure button is working because that wakes up the DC-DC converter which usually reads around 10VDC or so across the caps ( ei: C3). I also did take alot of time in this video discussing several Test points etc. which seems like a time waster to some and I know its hard to watch it all, but i did want to show some test points and other checks that could help someone as yourself with a different issue than mine. Great job on finding at least one issue! Hope it helps & Best of Luck to Ya!

[@blagojeciric32]

@@ThriftyToolShed Thanks for the reply and the info, I'll follow your advice. After some more probing on those 7.5Ah BMS boards I realized that T1 transformer, primary side, is open on both boards. I checked this few times and likelihood that I didn’t measure it right is small. Since I have 2.5Ah and 5Ah batteries I switched BMS from there and all is good so 2.5Ah, 5Ah and 7.5Ah are the same, however, 2Ah BMS board is different. I purchased few 2.5Ah batteries from eBay with the view to either use the whole board or to remove and reuse the transformers or other components as needed. Hope is that transformers are good. I noticed some other folks is responses to your video had issues with the transformer too. I really enjoyed your videos, and I found them very informative and good. Fixing electronics is my hobby too, I don’t like SMD but there is nothing I can do about it. Thanks again for the help.

[@ThriftyToolShed]

@@blagojeciric32 like you mentioned it has been a surprising amount of comments of people with the transformer issues and I have not personally seen that myself. I have been asked many times about help identifing the part. Although I tried, I could not find any info even if I pulled the can off the windings. So hopefully the 2.5ah packs do have the same transformer. Great job troubleshooting. I am still learning SMD soldering and it sure shows at least it is not as hard as I on e thought it would be. best of luck and thanks for your nice comment!