Faulty Milwaukee Fast charger | Can I Fix It?

In this video we're going to be taking a look at a Faulty Milwaukee Fast Charger. I purchased it from eBay for spares or repair, and it was listed as not working.
Caution should be taking when working with mains voltage equipment, due to the risk of electric shock.
I'm not an expert, but I do enjoy trying to fix things.
If you enjoyed this video, or found it useful or helpful, please consider subscribing. It's free and you'll be notified when I upload more videos.
Thank you for your support!
Some of the tools I use:
The Famous Blue Mat: amzn.to/47bPNGK
170 piece electronics tool kit (security bits): amzn.to/3FGLWpr
Aixun T3A Soldering Station: amzn.to/3u2SBri
Infiray P2 Pro Thermal Camera: amzn.to/47c05Xm
Soldering Flux: amzn.to/3Qn8Yq7
Low Melt Solder: amzn.to/3QICZ5r
Component Tester: amzn.to/46UcHm6 alternative (slightly cheaper) amzn.to/49yZSzJ
Overhead Camera Mount I Use: amzn.to/3tX8Ar4
Microscope Light (I use on my Trinocular): amzn.to/3FEAPgy
AD409 Pro Microscope 10" Screen: amzn.to/3G0CI7P
Extra Long Torx Drivers(used on Milwaukee radio): amzn.to/40siUU3
DC Power Adapter plugs 38 PCS: amzn.to/49lCUMm
#electronics #electronicsrepair #repair #milwaukeepowertools
Milwaukee Fast Charger Repair
Milwaukee Fast Charger not working
Milwaukee M12-18 FC Repair
Milwaukee Fast Charger Fix
Fixing a Milwaukee Fast Charger
Repairing a Milwaukee Fast Charger
Faulty Milwaukee Fast Charger

[@jansmit4628]

When mounting selftapping screws, it is a good practice to place them manually, then first rotate them counter clockwise until you feel a click, then mount it clockwise. By doing so, the screw does not create a new path in the plastic or metal but runs (most of the time) through the original path.

[@BuyitFixit]

Yes, I do this pretty much all the time especially when screwing screws into plastic. I saw it on a video years back. Works for non self tapping screws too. What happened here was that there was goo on the threads of the steel screw which stripped the threads in the aluminium as they originals weren't self tappers. The heat sink was actually tapped. Thanks for the tip though, as I might not have known 👍

[@michaelbraaten]

Great advice! Thank you for sharing that!

[@fouroakfarm]

Hadnt read that before. Thanks for the tip!

[@tmorton922]

I call it backthreading . Good point

[@MikeyMack303]

I really like your approach to electronic repair! I noticed, many years ago, that the most common problem was bad connections.... mostly, bad solder joints! Thank you for what you do!

[@BuyitFixit]

Thank you for your kind comments, and you're very welcome 🙂👍

[@safcforme]

Nice surprise to hear a local accent and even nicer to hear 'zener' and 'aluminium' pronounced correctly lol

[@BuyitFixit]

Thanks 😂😂😂😂

[@Ea-Nasir_Copper_Co]

@@BuyitFixitI’ve always wanted to ask where specifically your accent is from. I live in Western Canada where, in an area nearly the size of Western Europe, everyone who speaks English as their mother tongue speaks with the same accent. The CBC has a lot to answer for.

[@ralphj4012]

Only one Freudian slip with zee (26:38), nobody's perfect, ho, ho.

[@jason7741]

​@@Ea-Nasir_Copper_Cobest guess from me is North East England, i.e. Northumberland

[@BuyitFixit]

It's a Geordie accent. It's north east England around Newcastle. I grew up in a town called South Shields which is just slightly South of Newcastle.

[@JoBo-ug6tf]

You sir, are a madman: You completely reassembled it before verifying it worked. I salute you! 😅

[@BuyitFixit]

😂😂😂 I usually have quite good luck (or I'm over confident). It does sometimes bite me though, like on the JVC valve HiFi video I just did...

[@JoBo-ug6tf]

@@BuyitFixit I saw... You didn't do nearly enough groaning as I would've! But in fairness, you kinda had to reassemble it in order to test it. Maybe not put the cover back on tho! 😄

[@BuyitFixit]

@@JoBo-ug6tf The power of editing 😂😂😂😂

[@braixeninfection6312]

That is the only way. If it doesn't work it just means more pain. And pain is gain!

[@JFEnterprize]

@@BuyitFixithave you had a rapid charger that when plugged in with no batteries on to charge it blinks red and green and doesn’t charge a battery if one is put on the port? I charged one of my 5ah on my gf dual port rapid charger. The 48-59-1802 unit to be exact. It now blinks red and green on the bay I used whenever it is plugged into power. Any idea how to fix it? Havnt found a video of this yet. The battery itself I use all the time with no issues with other milwaukee chargers and it functions no issues. Just when I used her charger it seemed to “break” it

[@stef2198]

This channel is amazing, you are giving people with little or no electronics some confidence in how to go about fault finding. Respect to you sir.

[@BuyitFixit]

Thank you 👍

[@plasmaDave]

A mystery to me why this guy hasn't got more subscribers, I mean he's very good and subscribing is free ffs

[@BuyitFixit]

Awww thanks plasma Dave👍. Yes I know what you mean, I used to get quite disheartened over it as I did a video quite sometime back on an old firefox F7 videogame. I think it got around 250 views and a similar video around the same time got 500k views 🤷‍♂️ anyway channel is slowly growing..It's actually a fair bit of work to do videos and quite time consuming. Trawling Ebay for interesting items, testing them (I've had some that work fine), ordering parts, editing video, and not to mention the time actually diagnosing and repairing 🙂👍

[@plasmaDave]

@@BuyitFixit I have a tiny channel and getting even 1k subs is seemingly impossible. I'm not that bothered really though but agree it is an awful lot of work.

[@BuyitFixit]

Keep at it mate, I felt exactly the same 👍

[@AubsUK]

This post made me check if I was subscribed. I wasn't, but I am now! Thanks for the reminder 😁

[@jasonvandervalk3679]

I agree! Not many people can do this kind of repair. I watch alot of tool channels and none are this detailed

[@Mymatevince]

Really enjoyed the fault finding on this one Mick, well done!

[@BuyitFixit]

Thanks Vince 👍👍

[@inothome]

Love the "Yesssssss", nice one! I have never seen a flyback IC and switch in one package before or never noticed one. Nice how it's all integrated and makes sense.

[@akdenyer]

I have fixed a few of those. I have one with a failed transformer. I keep the chips in stock. I might data the transformer and rewind it for fun. I do have 2 winding machines, just got to make the mandrel to hold the bobbin. Good fun fixing this stuff.

[@BuyitFixit]

Nice 👍Thanks for commenting 🙂

[@user-fl6ug2fu4h]

Do you know where i can buy a transformer?:]

[@MultiReadify]

I love your channel and I'm so thankful you share your knowledge and experiences... but! I have a question... how does someone with your skill level and a Fluke 179 (quite expensive) not have a vacuum de-soldering tool such as the Hakko FR-301 (the model number changes based on the type of plug and if its 110 or 220v)? It is a life changing tool for me and makes de-soldering a breeze. You stick the tip around a pin, it melts the solder, then you pull the trigger and all the solder gets sucked out and into a removable chamber you can dump out later. It even gets the solder from down in the hole of the PCB so its completely clean (it takes a little practice to get it perfect each time). I sincerely hope you have not seen one of these and this comment is a great contribution to your talents. Either way, keep making these videos.. I'm learning so much from you!

[@BuyitFixit]

Thanks 👍I have seen those before, I had thought about getting one but a lot less things seem to use through hole components these days and more seem to be using surface mount. I've just recently got myself a new hot air rework station, so I still may invest in one in the future. Thank you kindly for the advice and the support 👍

[@Blacklab99]

You are a genius my friend. It’s a pleasure to watch you work.

[@BuyitFixit]

Thanks Steve 🙂👍

[@positivefix]

I bought one of these as spares or repair, almost as good condition as this one, when it arrived I plugged it in, put an M18 battery on and it charges fine, tried an M12 and that charged too. Been working fine ever since.

[@BuyitFixit]

Nice👍 I too have bought a few things from eBay like that. Only problem for me is that they don't make very interesting videos when I start recording and it's "oh.. it's working fine..." 😂😂😂😂

[@digitalwoodshop]

Great Video. The explanation of the various areas helped me understand the power supply better. Good Fix. Glad you covered the Safety info.

[@BuyitFixit]

Thanks 👍

[@adambikes65]

Good fix! I've had a few rapid chargers fail, one was the mains voltage switcher and another was the dual diode. The rapid chargers seem to fail a lot (lots on ebay for spares) and I've had them fail at work. Maybe they run too hot. I've had my standard rate charger for many years without issue, I like it more than the rapid because I feel it's better on the batteries at the lower charge current.

[@BuyitFixit]

Thanks Adam 👍interesting about the rapid chargers failing more often. I also suspected the switching IC 🙂

[@Enjoymentboy]

Agreed. I'm not a fan of fast charging and I'd rather the expense of a second or third battery for quick swaps but charge slower and extend the lifespan of the batteries.

[@histguy101]

Good job! If you take a bad charger to Milwaukee for warranty, they'll just dump it and give you a new one, when it's probably very often a simple fix.

[@BuyitFixit]

Thanks 👍I've seen expensive equipment being thrown away before and as you rightly say it's often a small part that costs pennies.

[@stopthebus]

These things are mass-produced in china, so they're cheap. It costs the manufacturer less just to give you a new one than to have someone (in reality quite a few people) sitting at benches repairing the broken ones. This is how it is pretty much with anything made in china now. They don't even have quality control in the factories. You the customer is now the QC. Cheaper to do this and just give you another unit than it is to pay dozens of people sitting on production lines to test each unit.

[@Sibbe2560]

My favourite repair channel…👍👍

[@BuyitFixit]

Wow, thanks!

[@artursmihelsons415]

Great video and excellent job! 👍 To prevent bangs, I'm running unknown or repaired mains circuits through my bulb box with switch selector for different wattage.. 😉 It's day saver, especially, when something faulty goes unseen at first look.

[@BuyitFixit]

Thanks. I'll have to get round to making one 🙂👍

[@SanelKeys]

I'd suggest you to consider using isolation transformer and series lamp on input, when doing repairs. Less scary.

[@BuyitFixit]

Yes, I really need to get round to doing that, although it probably wouldn't be as entertaining😂. Thanks for the advice👍

[@marbella-elviria]

Experienced people can work on live circuits all time without any risk. I repaired TVs before semiconductor took over and it was all live.

[@SanelKeys]

@@marbella-elviria why doing risky if you can avoid it?

[@inothome]

@@marbella-elviria LOL, a little cocky are we? No matter your experience, there is always a risk with live circuits. Everyone makes mistakes and having that attitude is what gets "experienced" people killed.

[@kareno8634]

Even if i don't know workings of electronics, i find watching electronic work, whether successful or not, Interesting. One day i may understand this and what's parts are to Fix the Dead. Nice job, *Thanks!* Cheers

[@BuyitFixit]

Thanks 🙂Have a look at the video I did on the switch mode power supply. It's works the same as this pretty much and I explain how it works and what most parts do👍

[@kareno8634]

@@BuyitFixit Thanks! i will

[@jasonvandervalk3679]

I only discovered your channel I like how you fix things that other people would throw away. Great work. I find it weird so many Milwaukee tools. I own 11 m12 tools. Most of my tools are dewalt. And now have m18

[@BuyitFixit]

Welcome aboard! When I started the channel I repaired a couple of Milwaukee tools that I bought broken from eBay as I was expanding my own collection. If I had a few Dewalt tools to start with, I'm sure you would see a lot of broken Dewalt tools instead 🙂

[@jasonvandervalk3679]

@@BuyitFixit so far I haven't had many problems with my dewalt tools.

[@InssiAjaton]

I would put some heat shrink tubing on the probe tops, leaving just 1/8" or 3 mm at the very tip not insulated. That way the danger of unintended touching would be greatly reduced in the live voltage measurements. Another handy thing comes from Big Clive - he takes photos of both sides of the board and prints one as is, and the other one mirrored, so both appear as seen from the same side and pads matching. Often he then inks component outlines on the solder side picture. That makes his reverse engineering and probing much easier. One more note is about the conformal coating applied on the board. There are 3 common choices, 1) silicone that is soft and easy to punch through, 2) urethane, tougher, and 3) epoxy, nearly impossible with just probe tips. I have had my battles with an Exacto knife, a surgical knife and sometimes even my Dremel!

[@BuyitFixit]

Thanks for that 👍Yes someone else suggested about the heat shrink on the probes. I meant to get round to it, then totally forgot. I watch big Clive too, and have seen where he takes the pictures of the boards when reverse engineering 🙂 I had an electric toothbrush which the wireless charger was all potted with epoxy. I was going to have a look at it but it was virtually impossible to get apart. Thanks for commenting 🙂

[@jeisonsanchez4842]

I really enjoyed this repair video. It gives me some ideas on how to troubleshoot an LPS65 power supply. It’s making a clicking noise and only outputting up to 2v every time it clicks. The expected voltage is 24v. Unfortunately, the bottom of the board has a light protective coating that makes it difficult to get a reading on the multimeter.

[@BuyitFixit]

Bootstrap capacitor? Small electrolytic usually next to the switching IC is a common cause of those symptoms...

[@jeisonsanchez4842]

@@BuyitFixit Thank you for the hint. I do see two small electrolytic capacitors next to the switching ic on a sub board. The sub board is soldered perpendicular to the main board and the components are hard to reach due to tight spaces. I will still give it a shot when I get a chance.

[@solomongainey838]

​@jeisonsanchez4842 were you able to get it repaired?

[@MarkusG101]

Thank you :) This helped me repair my charger. In my case the double Diode (10A per leg btw) one side was shorted. Also the little glued in fuse near the red charging cable. Replaced both and it's working :)

[@BuyitFixit]

Awesome 👍well done on fixing your charger 👏👏

[@user1766swl]

Hi. Use 40W Edison lamp in line for the test start. Safe and no more pcb damage in case off remaining problem.

[@BuyitFixit]

Thanks 👍Yes a couple of people also mentioned a "dim bulb tester" I should really get round to building one.

[@michaelbraaten]

I have a standard Milwaukee charger that died on me as well, before I was comfortable trying to repair electronics… I don’t remember if I still have it or not, I’ll have to rummage around to see if I do. I prefer the super charger regardless, as I use my Milwaukee tools at work, primarily.

[@BuyitFixit]

They are pretty similar. The other charger I was experimenting with a few months back was the standard version.

[@dlggamer7014]

Connecting a series lamp , u could determine if the input circuit ( before the transformer ) or the output circuit is at fault, its just gonna make your job easier eliminating one part of the board

[@BuyitFixit]

Thanks for the tip 👍

[@simontay4851]

UF308 is an ultra fast 3 amp diode. Looks like its part of the primary snubber network.

[@BuyitFixit]

Thanks for that Simon 👍

[@wurgervomlichtenmoor5073]

In single switch flyback converter you have mostly an RCD or Zener diode clamping network over the primary winding to convert the engergy stored in the stray inductance into heat.

[@hunger.for.adventure7440]

Omg A) this video was great and absolutely full of information. B) mate not only did I have the same presenting problem. My D7 was shorted out by a mosquito! I literally removed it's little electrocuted body and it started working again

[@BuyitFixit]

Thanks 👍Really glad it helped and you managed to fix your charger 🙂

[@kevwills858]

Enjoyed your fathoming and success .. My fast charger has stopped like yours but Im not an electronics wizz like you 👍👍. With what you knoe now, in hindsight, Is there a different order of testing you would follow now ? Just wondering if those diodes are a common fail ?

[@BuyitFixit]

There are pretty much a switch mode power supply. I've fixed a few of those on the channel so far. I'd check the diode, and another common failure is the TOP256 (I think it was) switching chip. I'd also check the bridge rectifier and the fuse as if the TOP256 has failed it can blow these too. I did do a 12V Milwaukee charger which turned out to be a tiny resistor.

[@Dutch_off_grid_homesteading]

Heya,that was quit a search but a diode unther some glue is difficult to spot still a nice repair with perseveranewell done

[@BuyitFixit]

Thanks 👍

[@VolkerLorenz-mj2wm]

Good video. Please look for a isolation trasformator like others wrote. And always change the 2 small electrolytic capazitors besides the IC on the heat sink. They are often the cause for semiconductors faults in primary side. These capazitors loose very often the value and changes the esr value too.

[@BuyitFixit]

Thanks. Yes isolation transformer is on my list. Agree I've changed those bootstrap capacitors in TV PSUs quite often in the past and are often a common issue. This seemed relatively new so I think they will be ok.

[@inothome]

I have looked for isolation transformers here in Vietnam in person and online and can't find any. So what I did instead is bought a 6A RCD and single DIN box and I use that inline with whatever I am working on. Best I could do and better than nothing. RCDs are ridiculously cheap here too, around $7 USD. Compared to $50 or more in the US for the same exact DIN rail breaker. Fortunately, I haven't actually tested it works well, yet.... Since I have been using it I haven't juiced myself. But, I'd rather an isolation transformer if I could find one.

[@stopthebus]

@@inothome What is the trip current of your RCD? 30 mA or 10 mA?

[@inothome]

@@stopthebus 30mA, better than nothing at all.

[@inothome]

@@stopthebus 30mA, better than nothing.

[@calmauric8218]

This is very useful. The bridge rectifier in my charger failed spectacularly. But im going to replace that component and try salvage the burnt area

[@BuyitFixit]

Thanks and good luck 👍

[@calmauric8218]

​@@BuyitFixit Update. The rectifier got her up and running again. Just the M18 side won't charge now. M12 works fine. Any advice? 😅

[@BuyitFixit]

I'm not so sure on that one, does it flash or anything or is there any voltage on the output? I can't remember if it's one output voltage that is regulated up and down or two separate ones.

[@calmauric8218]

@@BuyitFixit I've got 19.5v, and 10.58v on the DC side, if I slot in a M18 the led goes red as if it's charging for say, 60 seconds. Then it stops charging. No issues on the m12 side. Perhaps I need to desolder and test more individual components? It's almost like the charger is not doing the handshake with the M18 bms

[@BuyitFixit]

I did a bit work on the protocol about 9 month back on reddit. Theres a tx and rx line that go through a couple of transistors and then to the battery terminals. If you have a scope you can see the data..it starts off like a 1010101010101 then a pause then data gets exchanged.

[@wisher21uk]

Brilliantly fixed yet again Mick, why they cover diodes with glue I don’t know, does nothing to help it cool….I have had power supplies from TVs hold a good charge for a week or so, I found out the hard way hand straight over the the filter caps, my arm hurt for the day 😊 P.s if you need tv boards let me know, is there any other way to contact you ?

[@BuyitFixit]

Thanks mate, yes I had a bit of a jump with a capacitor the other day (you'll see it on an upcoming video in the next couple of weeks). Yes on the channel about page, there's a button "for business enquiries" which will show the email address (youtube doesn't show it on mobiles for some reason though). Cheers 👍

[@wisher21uk]

@@BuyitFixit I will have a look thanks ☺️

[@wisher21uk]

@@BuyitFixit nope nothing there on my ipad 😡lol

[@canyondan]

The Sherlock Holmes of circuit sleuthing. Well done.

[@BuyitFixit]

Thanks 👍

[@bramcoteelectrical1088]

😊Love your work. I am a professional electrican but like to tinker and fix stuff for hobbies at weekends so like to learn how to go about electronic repairs😊 thankyou

[@BuyitFixit]

Thank you. I'm no professional but I do seem to have a bit of a knack for fixing things 🙂👍

[@bramcoteelectrical1088]

@@BuyitFixit definitely I am watching your Stamford Stamford genny video learning about that so thankyou

[@leonidbreshnew401]

To protect Top256 mount a P6KE200A transil diode in parallel with 68K resistor (ZD 12 is shown on the PCB), milwaukee probably planned it on PCB, but then made some savings....

[@BuyitFixit]

Thanks for that. Much appreciated👍

[@carltonlane8931]

I’m really enjoying these videos,keep them coming

[@BuyitFixit]

Thank you 👍

[@markmaker2488]

3:00 Was there a video on reverse engineering the protocol?

[@BuyitFixit]

@@markmaker2488 I was going to do one, and posted a lot of my findings on Reddit, then someone called tool scientist took all of my work and made a video.

[@markmaker2488]

@@BuyitFixit Ive never heard of tool scientist. I think you should still do a video on it. FYI You’re my favourite ee channel on KZbin.

[@BuyitFixit]

Thanks mate 👍

[@bobbygeorge77]

Tremendous skills Mick.

[@BuyitFixit]

Thanks mate 👍

[@raymiller5738]

I did the same fault same repair same diode went short circuit... It would appear either a bad batch of diodes or it is underrated?

[@BuyitFixit]

Interesting, could well be either. I can't remember if the diode I used as a replacement had a slightly higher specification or not.

[@twistedhillbilly6157]

I don't know if this would be in your wheelhouse or not,, BUT what would it take to convert a plug in AC model to a DC model powered by an automobile 12v power socket (Cigarettes lighter).. I sometimes use an inverter, but I'd like to eliminate the extra component..

[@BuyitFixit]

I'm not sure if it's possible without a lot of mess on. The psu has two outputs. One runs the logic and the other charges the battery. I'm not sure if it adjusts the charge voltage for 12v and 18v on the main PSU. Also it has current sensing. I had been thinking could you use a boost converter to boost 12v to 18v but then if you put a 12v battery in it might send 18v into it instead of the 12 as it wouldn't be able to control the boost circuit, also it wouldn't be able to monitor the current unless you added or changed the circuitry to do that.

[@mag1vl]

Hello from Australia 🙃 I also have 1 of these chargers not working (M12-18C) looks the same as the 1 in the video but the inside is quite a bit different and the back of the circuit board is coated with some clear super tuff plastic coating..

[@BuyitFixit]

Hello from the UK. Yes the 18C (standard charger) is slightly different inside compared to the fast charger. The coating is called conformal coating and is to protect the board from moisture.

[@mag1vl]

Thanks for the info very cool@@BuyitFixit

[@5338ipv]

Finally found someone whohas a drive like me to fix everything they can

[@BuyitFixit]

Yes👍I'll have a go at pretty much anything.. and why not! It's already broken after all 😂😂😂😂

[@aldenorabrantesfilho4086]

i've one blowing fuse as soon as you plug it in....any guess what should i be checking ? great video.

[@BuyitFixit]

Yes, check the bridge rectifier and the MOVs at near the power input for shorts, next would probably be the switching IC attached to the heatsink. Pretty much the way I started checking this charger.

[@clownhands]

Greetings from New York. Just found your channel and loving it. Based on how much time is left in the video I get a sense how close you are to the solution :-)

[@BuyitFixit]

Awesome! Thank you!

[@stevewade6438]

I've got 2 of these broken . Was it just that diode in the end then ? I may open mine and check that first

[@BuyitFixit]

Yes, just the diode on this one. Another common problem is the main switching IC.

[@tonynobrega9115]

⁠​⁠@@BuyitFixitwhat’s the main switching IC ?

[@kristene2372]

Just a heads up when the green light is flashing not finished charging until the light stops flashing

[@BuyitFixit]

Thanks👍, yes I eventually discovered that on the label on the front 😂

[@GeneralRepairService]

Les comparto detalles, es una da las fallas más comunes en un cargador Milwaukee, en el cargador Milwaukee Charger M12/M18 el integrado es: 1826 TOP266EG 7F849B, DE 6 PINES, mientras que en el cargador Milwaukee con solo entrada de batería M12 es 1446 TOP255EN 3S795B De 6 pines, ligeramente menor potencia pero ambos son compatibles, saludos de General Repair Service.

[@BuyitFixit]

👍🙂

[@simonrawle7885]

I did see that post on Reddit. Was a interesting post on the protocol

[@BuyitFixit]

Thanks Simon. I had been going to do a video on it, but wasn't sure if people would have been interested.

[@shepherd1006]

Its a pity you don't live next door great work

[@BuyitFixit]

Thanks 👍

[@cliveparkes4052]

Why do you remove a fuse to check if it's open circuit it can be done in circuit easily

[@BuyitFixit]

To show people who may not know how to test a fuse.

[@cfq.tufanuf7601]

I purchase a lot of these charges mainly Bosch (faulty ones) and 90% of the time it's a faulty diode

[@BuyitFixit]

Interesting, thanks for sharing 👍

[@jackrees5325]

What happens when you put a 12 and 18v battery on charge mine gose into over heat protection not sure of its ment to do one at a time iv not investigated why as it works fine one at a time

[@BuyitFixit]

Weird, I don't think I've had that, but then I'm not sure if I've tried both types of battery at the same time.

[@chrissmith7655]

Hi, excellent work and very interesting. Many thanks from Nr Chester.

[@BuyitFixit]

Many thanks, glad you enjoyed it 👍🙂

[@krahwinkel9503]

When the M18 is fully charged the LED is flashing while on the 12V side the LED remains steady when the M12 is fully charged - bug or feature ?

[@BuyitFixit]

No idea! I didn't notice until you pointed it out. My bad it seems. I just checked the front of the charger and it says flashing green is "nearly fully charged" so I guess I jumped the gun on it and thought it was fully charged which is steady green!

[@in2dodo744]

Thank you so much! It's a very interesting video! You show us all the process! A very good vidéo

[@BuyitFixit]

Thanks so much👍. Yes I do this to help people learn what I know and hopefully repair their own devices 🙂

[@merlin5476]

My Milwaukee charger is a model c18c & the 4 pin regulator thats heatsink mounted has blown apart & i dont know the type of regulator it is... any idea what it could be?

[@BuyitFixit]

Is it only 4 pin? Most of the chargers seem to use a TOP256EN which is 6 pin.

[@merlin5476]

@@BuyitFixit opps !!!! Just re checked & it is a 6 pin 👍 I shall now and hunt 1 down & keep my fingers crossed. Many thank 👍👍

[@BuyitFixit]

You're welcome. Glad to help. I'd maybe check other components too such as the bridge rectifier and other diodes just in case they were damaged when the IC shorted.

[@martinkarafin4640]

Hey, I got a hold of two of these. I managed to fix one, it only had a faulty double rectifier diode. The other one is putting up a fight though. It had the same failed double diode, replaced it and it will briefly power on now. If I put a battery in it it will blink red/green for a second or two and then die and wont power on again until the caps are empty. When measured the low side caps will be at 10V and the drop to around 3V. It does this regardless whether there is a battery connected or not. Any ideas?

[@BuyitFixit]

Sounds like something on the mains side, You should have more than that on the output caps if I remember. I'd just check resistors etc on the main side. I had a small SMD one fail on another charger (think it may have been the 12v charger I looked at) near the opto coupler.

[@zs1dfr]

Thank you for this adventure into deductive reasoning. As a matter of interest, would testing the primary and secondary voltages at that transformer between the "hot" and the "cold" side of the PCB have given you any ancillary information?

[@BuyitFixit]

I haven't had much success measuring voltages directly at the transformer because it's high frequency AC and the meters don't usually work well with it.

[@zs1dfr]

Ah, right. Thank you. Some more scales have fallen from mine eyes 🙂@@BuyitFixit

[@snipersquad100]

Why don't you put a 60-watt light bulb in series with the DUT when switching on for the first time after the repair, it won't go bang then if it's still broken.

[@BuyitFixit]

Good idea, a few people have suggested similar. I don't think I've got any incandescent bulbs.

[@generaldisarray]

Excellent work as always

[@BuyitFixit]

Thank you so much 😀

[@Trucam2020]

Thanks for sharing this video

[@BuyitFixit]

My pleasure, and thanks for commenting 👍

[@rory9174]

Brilliant and thanks so much, really enjoyed the search for the fault. I notice you use a flux called Kingbo. Would this flux be comparable to Amtech ?

[@BuyitFixit]

Thank you 👍Not sure as I've never used Amtech. I just got it from Ebay because it was cheap 😂😂😂 It seems to work OK but I find it a little hard to squeeze out of the syringe as it seems quite thick...

[@rory9174]

@@BuyitFixit The world is full of fake stuff. I've bought Amtech from 2 different sources and both are fake, they evaporate the second heat is applied. I'll give the kingbo a shot. Looks good from seeing it on your videos. Thanks again.

[@BuyitFixit]

No problem, glad to help 🙂

[@NicksStuff]

17:00 It shows *negative* ohms?

[@BuyitFixit]

Probably charge in a capacitor throwing the reading off. If there was a short, it would still show it on the meter.

[@NicksStuff]

@@BuyitFixit But what is a negative Ohm? Isn't that a bit weird?

[@BuyitFixit]

Yes, I think it works by measuring the voltage it sends across the resistor so if there was a charge of the reverse polarity it would throw it off. It probably does the negative to show you this as if it didn't and just showed 0 you might think it was a short, although alternatively it could Err or something instead.

[@NicksStuff]

@@BuyitFixit I guess that's an issue when the circuit is energized (by mains, a battery or a charged capacitor) but I would have hoped such an expensive multimeter would detect that and throw an error. Because if you swap your leads, you still have a wrong value but no minus sign, don't you?

[@richardtaylor7199]

Great job.

[@BuyitFixit]

Thank you! Cheers!

[@PowerScissor]

I have a pile of brand new looking dead Milwaukee chargers. Never thought people would be paying for them online. Adding up all my chargers that came in kits...its a 10% fail rate with no physical damage (never dropped, yanked, etc)

[@BuyitFixit]

Yikes, seems a pretty high failure rate. I wonder if it's a design fault or inferior components perhaps.

[@gregpetroski6333]

I know this is focused in repairing, but I was wondering if you think it would be possible to convert one of these chargers (rapid or the regular slow charger) to run on 12v? For charging in a car without running an inverter? Milwaukee sells one for over $100 but it's slow and it's expensive given they include the normal charger with basically everything. I must have 6 of these by now. Thoughts?

[@BuyitFixit]

I doubt it. You would need to boost the 12v from the car to the 20v or so that the charger requires, but then also the charger would need to be able to control the voltage and current of that booster. A simpler solution (although with power losses) would be to use a 12v inverter to power the mains charger

[@TheRealBobHickman]

Do you specifically look for Milwaukee tools to fix or are they just a lot less reliable than other brands?

[@BuyitFixit]

I had a few Milwaukee tools and wanted a radio, bought a broken one and fixed it. I then thought I'd get a few other broken tools to try and fix to expand my own collection and thought the videos might be useful to other folks too. If I had dewalt tools or such then you'd probably be seeing a lot of those instead 😂

[@TheRealBobHickman]

@@BuyitFixit That makes a lot of sense. I guess I won't avoid that brand then ;)

[@BuyitFixit]

@@TheRealBobHickman I wouldn't recommend the circular saws, as I've seen a few failures. The drills and grinders seem ok.

[@powertoolsrepair]

Your videos are great and very informative, but I like your cammera zoon, what cammera are you using fol filming?

[@BuyitFixit]

It's a sony HDR-CX450 with a third party wired remote. It means I can zoom and start and stop recording without touching the camera which is mounted overhead. I should start putting this info in the video descriptions as I've been asked a few times now 👍 If you have any other questions feel free to ask and I'll try my best to answer 🙂👍

[@powertoolsrepair]

@@BuyitFixit that cammers zoom is amazing good 🤠 Thank you very much

[@BuyitFixit]

@@powertoolsrepair you're welcome. They do a 4K version too but it's more expensive. I bought the one I'm using used from Ebay.

[@powertoolsrepair]

@@BuyitFixit and i gues you repaired it?😁

[@BuyitFixit]

@powertoolsrepair No lol 😂😂😂 I just bought it used and working. I think I paid around £85 before that I was just using an old iPhone 6 and using digital zoom in the editing software 🙂

[@user-te1le7ck6b]

Great work yet again

[@BuyitFixit]

Thank you! Cheers!

[@mikecass8306]

Great fix Mick, another bargain charger for your tools 😀

[@BuyitFixit]

Thanks Mike👍

[@PowerScissor]

Just a tip if anybody is interested, there are much cheaper 3rd party chargers on Amazon that have a display built in for pack voltage, charge %, charging current, etc. They are cheaper than Milwaukee ones, never had one fail, and they consistently charge packs that refuse to charge on OEM chargers when certain of Milwaukees own tools always discharge packs below what their chargers will accept. Started using them after I got tired of Milwaukee ones dying for no reason too often, and being overpriced for being "dumb"-ish chargers.

[@juanitoseme8632]

Thanks for sharing

[@BuyitFixit]

Thanks for watching!

[@zombieryder]

I had a similar problem after replacing diode the charger turned on but when put load on it would collapse.

[@BuyitFixit]

Not sure on that one. I'd check capacitors etc and try to eliminate if it's on the low or high voltage side.

[@zombieryder]

@@BuyitFixit all caps are good, replaced a lm358 wasnt giving right values. Im guessing the problem lies at low voltage. Im getting a 12.6v max probing, this is a 21v charger. Im not sure if it would boost up volt when a battery pack is detected. There are too many resistors lazy to check them all. The diode and lm358 was replaced on the low voltage side.

[@ricardoferreira2811]

Hello, have you ever felt the need to have/use a curve tracer for testing zener diodes? Thx

[@BuyitFixit]

Not heard of one but it sounds interesting...

[@whitcwa]

A power supply with the proper series resistor is all you need to test zeners. I have a Tektronix curve tracer, but don't use it often. It's great for finding leaky diodes and transistors, but that type of failure is pretty rare with modern components. I also use it to measure the breakdown voltage of parts.

[@BuyitFixit]

I usually find most semiconductors fail short circuit. Although it did seem that the transistor in the tyre inflator I recently looked at failed open at the B C junction.

[@RaithUK]

Nicely done fella.

[@BuyitFixit]

Cheers 👍

[@lmwlmw4468]

Nice work.

[@BuyitFixit]

Thanks 👍

[@hpd385tannoylover2]

Interesting vid and a new sub from me. I have a standard rate charger that has the same prob. Of course, the board is a bit different, but you have given me inspiration to go look.

[@BuyitFixit]

Thanks 👍If you get stuck with anything feel free to drop me a message 🙂👍

[@hpd385tannoylover2]

@@BuyitFixit Thanks a lot! Don't expect replies from a lot of tubers.

[@BuyitFixit]

@@hpd385tannoylover2 I do try to reply to all comments, at sometime in the future that may become too much for me depending on how the channel grows 👍

[@hpd385tannoylover2]

@@BuyitFixit Double edged sword. I want channels like yours to succeed, as you deserve it, but also I selfishly want you to stay accessible. 🧐

[@shanewright6385]

Hi can these be easily converted to 12v ? Thanks

[@BuyitFixit]

If you mean to power them, then no. You could use a small inverter if you want to run it in a car.

[@599miata]

Great job again mate.👍👍👍👍

[@BuyitFixit]

Thanks mate 👍🙂

[@olvano]

good job sir

[@BuyitFixit]

Thank you kindly 👍

[@DavoShed]

Never seen a fuse in a power plug like that. Guess rules in Australia and UK are different.

[@BuyitFixit]

Yes, all UK plugs have a fuse inside. The sockets usually go to a 32A breaker, and the most a device will draw is 12.5A which is 3KW. Hence plugs are rated at 13A, with a maximum fuse of 13A. You get fuses like 1A,2A,3A,5A,10A etc depending on the device.

[@DavoShed]

@ Very interesting. Most house hold power points in Australia are 240V 10A so I think they are limited to 2000W. Optionally you can install 15A outlets mostly for workshops and stuff like that. The sockets have a larger earth pin so you can’t plug them into a standard 10A socket unless you grind the pin down 🤠

[@BuyitFixit]

For workshops / welders etc you can get a round 16A or 32A socket and plugs over here. They look at bit like this m.media-amazon.com/images/I/51UcKcQ+VZL._AC_UF1000,1000_QL80_.jpg

[@wherami]

Always a great learning experience

[@BuyitFixit]

Glad to hear that! Thanks JS👍

[@irishlad8797]

Can someone please tell me what kind of head is on the 5 screws holding the charger together??? Iv tried flat head and Philips head but no go I think they might be trianglular ??? Thanks guys

[@BuyitFixit]

They are security Torx.

[@ChotuuSian]

Good work 👍

[@BuyitFixit]

Thank you! Cheers👍

[@mrvang8077]

I have that same charger and had only used it twice, then it just sat there for a long time, and it just went dead out of the blue. Makes me wonder if these are just poor quality charger. It's practically brand new.

[@BuyitFixit]

I think you could be right as I've seen a few of these on eBay advertised as faulty that also appear to be in pretty new condition.

[@mrvang8077]

It hasn't even been more than a year. And for it to just died because it was not being use as much is a sign of poor quality components being used. I'm not spending anymore money for a new one when this one I have is practically brand new. Milwaukee need to just give us a new replacement.

[@BuyitFixit]

The standard chargers seem much more reliable than the fast charge versions.

[@stopthebus]

Like just about every other mass-produced consumer electronic item, these are made in china to a price and not designed to last or be repaired.

[@waynetaylor2784]

Excellent video as always

[@BuyitFixit]

Thanks Wayne 👍🙂

[@oldguy8177able]

well done

[@BuyitFixit]

Thanks again! 🙂

[@tristanroberts1645]

Great work 👍

[@BuyitFixit]

Thank you! Cheers!

[@michaelbraaten]

Also, I heard the clicking of your soldering iron, that is basically what mine does too, so I guess it’s just the way they are lol

[@BuyitFixit]

Yes, I too heard it on the video that time. It's just the mosfet switching power to the element using PWM.

[@neiltheplayer]

just brilliant "again" 😀

[@BuyitFixit]

Thank you! Cheers!

[@cajuncoinhunter]

Looks like that diode did it's job protecting it's circuit ...... I have seen a few times that they didn't do it's job and some fet's or IC's like you took out , went up like fireworks ...... Take care Mon Ami ............

[@BuyitFixit]

Thanks Cajun 👍

[@BuyitFixit]

Is it really that important? I often make such mistakes, and English might not be everyone's first language.

[@cajuncoinhunter]

@@Kevin-mp5of I assume you are a teacher of some sort Mr. Kevin This comes from Grammarly and it's or it is in the books so to speak . What does it's mean? It's is a contraction meaning it is or it has. Just like in where's or there's (contractions of where is and there is), the apostrophe signals that two words have been combined. Remember, any time you use it's, you must be able to substitute either it is or it has in the word's place.Nov 9, 2022

[@cajuncoinhunter]

@@BuyitFixit That's right and anyone can tell that I'm French by the first name of my Channel , it doesn't really matter because I spelled it correctly .....

[@diabolo3506]

@@Kevin-mp5of "ça" it is not a possessive but a demonstrative pronoun. "sa" its is a possessive. ;)

[@DaytonaJim78]

How can I make this into a 20v power supply

[@markid2010]

whatcis that part you replaced please?

[@BuyitFixit]

29:41 UF308 - Shottky Diode. I replaced it with a UF5408

[@Lightrunner.]

Fast and charged repair ✌️👍🖖

[@BuyitFixit]

Thanks 😂😂😂😂👍

[@FixthisCD]

I have same one that works but it gives a high frequency noise. I don't leave it unsupervised ;)

[@BuyitFixit]

I've got another one, it sounds pretty much the same too.

[@LilasTools]

Great work! 👍👍

[@BuyitFixit]

Thank you! 👍

[@esbenarndt5703]

I think Milwaukee is by far the one brand you repair the most? Is it so bad?

[@BuyitFixit]

At the time of starting the channel, I had a few Milwaukee tools. They were quite expensive so I thought I'd save some money by buying some broken tools from eBay and repairing them to add to my collection, and hoped it would help others if they had the same issues. If I had owned Dewalt for instance you would be seeing lots of Dewalt repairs etc 🙂Hope that makes sense.

[@andymouse]

Awesome...cheers.

[@BuyitFixit]

Thanks Andymouse 🙂👍

[@LilasTools]

My rapid charger works fine but has a loud hiss when charging... i worrycits gonna blow up ever time i use it.

[@BuyitFixit]

Yes, I've got another one that sounds the same.

[@TiềnLê-x5f]

just repairing the milwuakee m12 and m18 charger with input power but no output power what's wrong

[@BuyitFixit]

I'd start by checking the voltage on the capacitors on the output side of the transformer like I did on the video. See if any voltage is present and either work forward if it is, or backward if not.

[@TiềnLê-x5f]

@@BuyitFixit when i replaced the double diode ,it output voltage intermittently, not enough 11v

[@BuyitFixit]

I'd probably start checking capacitors

[@TiềnLê-x5f]

@@BuyitFixit i replaced the capacitor and it's still the same i dont known where the problem is