Using a Memory Saver When Disconnecting Your Car Battery

In this video we show how to use a memory saver to ensure that your car’s subsystems do not lose power when you disconnect your primary battery. This is helpful if you want to ensure that subsystem settings (such as radio settings or computer parameters) are not lost when you disconnect your car battery.

[@ChristopherLum]

In case it is helpful, here are all my van videos in a single playlist kzbin.info/aero/PLxdnSsBqCrrF5nO7cmNTc4cct0miFWdO6. Please let me know what you think in the comments. You can support this channel via Patreon at www.patreon.com/christopherwlum or by clicking the 'THANKS' button underneath the video. Thanks for watching!

[@d.s.9632]

I recently tried to use a memory saver on a 2022 car. It was a cigarette lighter male plug to obd2 port. I used a 12v 10 amp source and I blew a fuse that was stating itself to be 7.5 amps. Now I am seeing you use a car battery that I believe produces way more amps at 12 volts. How the heck did you not blow a fuse? I think the solution for me is to use something under 7.5 amps between 4.5 and 6amps but im still worried about breaking something.

[@frankperalta887]

Best video I've come across re use of the OBD II battery saver. Mainly because it answered my question about the beeping while connected; I reasoned that it is a good reminder that you're hooked up to a backup battery, while replacing the main battery. Thanks for the informative video.

[@jeffreyhawkins9579]

Thank you for sharing what happened when the leads touched and blew a fuse. This helped me figure out what happened to me. Also as a possible helpful tip to those who do not like the beeping, I took my saver device apart and removed the beeper. God bless

[@d.s.9632]

As for me , I recently tried to use a memory saver on a 2022 car. It was a cigarette lighter male plug to obd2 port. I used a 12v 10 amp source and I blew a fuse that was stating itself to be 7.5 amps. Now I am seeing this video use a car battery that I believe produces way more amps at 12 volts. How the heck did he not blow a fuse? I think the solution for me is to use something under 7.5 amps between 4.5 and 6amps but im still worried about breaking something.

[@dominicfong6341]

Mr. Lum: thank you so very much for sharing the dos and don'ts, I would never have thought of such a mishap could happen. Yes that constant beeping is extremely annoying, maybe you should exchange for another one.

[@xarptwin]

Excellent video with enough information and helpful warnings. Thank you.

[@bobsoft]

I have a similar memory saver like yours with the alligator clips. It came with a 15A fuse on the positive lead. I have also added a diode to the positive lead to prevent back feed from the battery under the hood.

[@leoseries]

I used one of these to change a battery but connected it to a 9v dry battery instead. It worked perfectly. I made sure that nothing was left on -lights radio etc.

[@scrc511]

Great Vid. I’m actually thinking of how safe it is to have a 12v running on the OBDII port, but your vid had prove it. Thanks, I’ll be purchasing those memory saver cable.

[@surf6009]

I'm still not convinced it won't harm the vehicle. Spose I'll have to check with Scotty.... .

[@jamestone265]

Worked exactly as shown. I purchased the jumper from Amazon and replaced the battery in our 2018 F-150 and kept all the settings. The truck did not need to relearn anything.

[@djchi5]

specifically what battery saver did you purchase from Amazon. Thanks

[@frankyrubful]

Yeah I’d like to know which memory saver you used too ??

[@Jaguar_EType]

Never having seen or used a battery saver before the explanation and instructions were most helpful. I may now go and treat myself to one!

[@hs4u537]

Don't see the point of this as you will need 3 12v batteries.... 1. Main battery for replacement or to remove... 2. Battery for power saver... 3. The new replacement battery... I would invest in one of those car starter packs which you can connect directly to terminals

[@hs4u537]

Or unless you are removing main battery for space in engine bay! If it's just for battery maintenance or swapping out faulty battery I think this is the most useless thing ever

[@surf6009]

Good video. Thanks.

[@khvidtube1617]

When you disconnect the power to the OBD port, I think you want to disconnect the negative clip first then the positive clip.

[@sulla9528]

Same item sold on newegg and they say to disconnect positive first and then negative.

[@husseymangtv]

it says take off + first..... Finally, after replacing the battery, first loosen the red clip of the tool. If the tool is still ringing at this time, it means success. If it doesn't sound, it means the fuse on the car is burnt.

[@kirkbrown2147]

It doesn't matter which you take off first as long as you're careful

[@FloridaMan7337]

always neg cable first then last to go on

[@davidboreham]

The ordering of connections in cars is a myth. Source: electrical engineer.

[@guestguide2544]

If you have a small 12V car battery charger, you could just hook the battery charger positive to positive (opposite end of battery post/cable connection, where the + cable bolts to), and the neg cable of charger to ground on steel of body or engine block or where the cable itself connects to body ground.

[@anthonyvee]

Nicely explained. Thank you.

[@johnw6498]

Thank you for uploading this excellent video you did a great job explained a lot of things made it crystal clear all the best to you. 5*****

[@davidrowland3138]

Chris great video. Thanks for sharing your knowledge. My question is ho in the heck are you getting almost 17 mpg in your Transit, 12.8 is best I’ve seen since it was new.

[@pattie8744]

Great video and very helpful!

[@ChristopherLum]

I'm glad it was helpful. There are several related videos on the channel. Please feel free to check them out and I would love to hear what you think in the comments. Thanks for watching!

[@fabiobatalhadesa1586]

Congratulation Mr.Lum for vídeo... very very good, Thankyou!!

[@roxyroxy4816]

Great video, you sound a little bit like the late Steve Jobs.

[@EnigmaverseElysium]

Woah he actually does a bit! I cant unhear that now.

[@SpotandLes]

I have a Transit also. Thanks for the great video.

[@ChristopherLum]

I've got several other Transit videos on the channel please feel free to check them out. Thanks for watching!

[@d6487]

Great video. Is it safe to plug the alligator clips to another car's battery while the donor car is on with it's alternator running? i don't have a spare 12 volt battery sitting around. So this is my only option left.

[@richarddodson3620]

35.00 at a local junk yard for a slightly used battery.......

[@surf6009]

Cover the positive clip before you use the unit. Don't care if you use the Red Green show method, just please cover the positive until you are ready to clip it on.

[@sergiopabon1387]

Cool thanks for this video. I might get one since my corolla takes a long time to idle correctly after a battery change. Btw 6:17 Dada what are you doing. 🤣

[@waynehutchinson1423]

Thanks,for great video.

[@bmfilmnut]

I have this same battery saver. It didn't come with instructions so I went back to the Amazon page to see if instructions for use were there. Below is a cut & paste of those instructions. If anyone can decipher what they mean, they must be psychic. But the point I want to make is that it seems to say that if you short out the battery cables, you can actually burn out vehicle's ECM (ECU) which would be a disaster. They are VERY expensive. Also, when I ordered it, I realized that the alligator clamps could be easily shorted out and they require the use of a spare battery that you would have to use in the vehicle because of the short length of the wires. So I cut off the alligator clips and made a 12 volt power pack with a standard case that holds 8 AA batteries and has a 9V plug. I soldered a 9V plug to the battery saver's wires so I could connect to the battery pack I made. Some people report that a 9V battery will save the vehicle's settings to so you can try that but I went with the full 12V pack. (The battery case only cost a couple bucks.) Also, I'm not sure you are interpreting the beeping correctly. The instructions seem to be saying the beeping pattern should change and the Amazon reviews say it it should slow down when the connection is good. Who knows? The instructions are terribly written and it's obvious that some of the reviewers can't figure them out either. If I'm deciphering any of the instructions (below) correctly, it looks like they are saying to connect the ODB-II connector jto the battery BEFORE you connect plug into the ODB-II port. I'm not sure if that can make a difference - probably not, though, because you did it the opposite way in this video. Anyway, try to figure this out. This is an exact cut & paste of the instructions shown on Amazon: "★Operating instructions and notes: 1, with a red clip to connect the backup battery cathode, black to connect the negative (Positive and negative polarity will burn the car computer). 2, plug the red light, and then insert the car OBD plug, this time has been issued by the sound of drops, indicating normal connection. 3, at this time can change the battery, careful operation, pay attention to the replacement of the battery must lock the car, do not open the lights and other electrical equipment, not to the battery positive ground, otherwise it will burn the car OBD socket fuse. 4, for a good battery, the first release of the tools of the red clip, if also drops at this time ring, indicating successful, if there is no sound, indicating that the fuse burned."

[@ChristopherLum]

Bob, thanks for the very detailed feedback and comment. I'm going to pin your comment to the top so others can hopefully benefit from the information you shared. Thanks for watching!

[@curse_illusionss2871]

Bought the exact same one the instructions doesn’t make any sense at all all I can say is don’t touch positive and negative while the saver is connected to the obd port

[@vishwasomayaji3436]

Thank you for a nice video

[@andygrant6199]

I bought a memory saver to change a MkIV Renault Grand Scenic battery, but the OBD2 port was in none of the places that it shows it to be - I still haven't found it! Frustrated by this I made up a memory saver using two lengths of wire, with an in-line fuse in the +ve lead and proper crimped connectors at the ends. Insulated terminals MUST be used. This was conected to a 12v battery from a child's go-cart and each lead securely connected to the leads going to the battery, using additional nuts. Once done, connect the preserving battery in parallel and remove the terminations from the old one in the car, -ve first. When removing the +ve, wrap terminating wire in a plastic bag to prevent contact with any body metalwork - remember these are still live! The Car memory is now being held up by the preserving battery. Replace the car battery and reconnect leads. Lastly, remove the preserving battery, -ve first. Once everything is secure, the car should have its memory exactly as it was before.

[@njsongwriter]

If it has an ash tray look behind it for the OBD plug.

[@williambeatty5779]

Great Video Thanks!

[@cwejter]

Do I need a spare battery or I can just use another car's battery or lighter socket?

[@checkyoursix5623]

Don't have an extra 12V car battery around ? Hey, there's your lawn tractor, or garden tractor, or zero-turn. You might need longer cables, though. Or even two 6V large-type flashlight batteries in series.

[@daisyypoon]

What information will be lost if I don't use a Memory Saver like the one you used?

[@flaviokonti5522]

It depends on brand. I have Suzuki and its ecm settings reset and cars idles like crap, and I have to perform manual relearn. Using this procedure i dont lose anything. Only downside is you have to have one more extra battery, 3 in all, one in car, one for obd and new one

[@GeirGJohnsendto]

You did forget a very vital thing! You have to use a high end scanner to tell your computer that you have put in a new battery.

[@niacal4nia]

True on some newer cars such as BMWs. Older cars don't care.

[@PeterHernandez-lg2eh]

Have to be very careful with the red and black clips. If you mess up no bueno

[@derek40s]

So.. after a little research.. I found this.... " They are not effective or worth the risk. I-CAR also teaches not to use them.” Jeff Peevy, I-CAR's director of field operations, concurred. “A memory saver can complete circuits that removing the battery opens in order to protect the system, and so a memory saver could put systems at risk,” Peevy said.Jul 18, 2014".. any comments?

[@davidwoo2590]

Note, that's a piece about welding metal on a car body. Electric arc welding and it's a different story than if just replacing a battery.

[@BuscandoSanaDoctrina]

The switch in on or off? In the process

[@mikecochrane2074]

thanks for the video. can i use this kind of device to keep my baiid device powered on while changing parts such as a starter, alternator or any other electrical device on my truck, or does this send power to all those other things also? rendering my maintenance just as dangerous as having the battery connected?

[@Kartraceone]

One warning that you failed to mention is thst when you start feeding 12v frim the back up battery the you have to make sure your msin battery terminsl is snt going to touch ground eed to be done with caution

[@TN-bm6dh]

What if I don’t have a spare battery?

[@rudychavira5558]

Mr lum, to replace battery on my 2017 rogue, is another battery needed to plug into memory saver? And are memory savers for specific vehicles or any will work?

[@robertosibulo2548]

during your battery replacing and while there was installed obd2memory saver.do you install and replace when the ignition switch was off?

[@robbocop33r12]

I just bought a lithium battery car starter,similar to the Noco genius,it charges things like smartphones etc too. Would i be able to use it as a direct source of power to the obd if i found an adapter?? Im thinking maybe yes?Great video!

[@johnbielenda7336]

yes you can, but the memory saver would have the cig. lighter end and the obd end........cig. lighter end goes into the car starter and turn on......works fantastic.

[@g2145cal]

@@johnbielenda7336 i am about to do this, but the GOOLOO jump starter/power bank has an output of 16.3 volts (tested with my craftsman volt meter)...i am hesitant to put 16 volts into the OBD port.

[@OldSchoolNoe]

@@g2145cal Just buy the simple 9V battery adapter, costs ike 15 bucks, goes into the cigarette lighter

[@g2145cal]

@@OldSchoolNoe I just went for it and replaced the battery without the saver or Gooloo hooked up...nothing adverse happened, just one prompt on the display. All is good.

[@hg2.]

Thank you!

[@ChristopherLum]

You're welcome!

[@samkitty5894]

This may not save your dashboard clock time or your radio presets. I connect spare battery to the terminals and keep them there while replacing bad battery. This way nothing is lost...

[@jthuff5102]

Why not just use jumpers cable that you already have to the terminals under the hood

[@fordprefect4345]

That's what I do

[@mindlessgreen]

Many videos on how to do this. No explanation on why. What is being saved? What happens if you change the battery without this?

[@jmont6638]

Several things can happen, the most annoying is your car won't idle correctly and it will die after a second or two, you start it again and give it gas , but it dies again and again. The procedure to re learn the idle settings varies from car to car and it is time consuming. Then you can also loose other settings in the electronics, like your radio , clock, and others. On very expensive cars I've told you have to take it to the dealer so they can reset things for you and of course it is not free.

[@giovanhagar]

Lose your radio presets? Clock? Hook a battery maintainer or trickle charger to the battery cables before you remove them from the battery and leave them on until you put them back on the new battery.

[@anthonyguada]

I dunno... Does it take someone longer than 30 Minutes to change a car battery EGADS.. just heard you say, We could blow a fuse using your method. Great Scott And besides I do not have a spare battery

[@b374mxg]

Where did you purchase it? Thanks

[@identifiesas65.wheresmyche95]

If you had a device with long enough cables - couldn't you just hook it up to the same battery you're disconnecting? Or is that no good?

[@identifiesas65.wheresmyche95]

@torTxoFognaTuluZ you're not gonna get shocked. As to the terminals getting in the way, idk about cars in general but on mine at least you can leave the battery cable clip on and just remove the cable from the terminal clip. If your battery cables are soldered on to them on the other hand... yeah that'll be hard.

[@lstanich1]

Perhaps I’m missing something but why not just clip a 12vdc source a couple inches south of the car battery’s positive cable and clip the source’s ground to anywhere convenient? No need to purchase anything …

[@alexwolf8019]

Can we just use the same battery already in the vehicle? Will it double voltage the OB2 that way? I dont need a new battery, Im just doing some work around it.

[@975na]

maybe the wire is not long enough

[@jjjohn5914]

I dont have a spare battery

[@lmt200ish]

Instead of having a spare battery to connect to why not get a 12v DC power supply and wire it directly to memory save.. It easier to plug it in instead of having a big 12v battery around.

[@ronsorrentino6207]

I thought about doing that too but if your power goes out, and with my luck it would, guess what? lol

[@njsongwriter]

You can simply use a 9 volt battery.

[@lmt200ish]

@@njsongwriter I made one with a 12v power supply and works great.

[@fabiobatalhadesa1586]

I'm from Brazilian...

[@charlesmitchell487]

Not much good for replacing your battery (unless you have a spare 12 volt battery lying around...)

[@fourthtunz]

I'm trying to do this today, you need 3 batteries really

[@ryancasing9299]

I kept the alligator clips separated and when I pulled the cord to plug it in to the bod port the wire moved and made contact between the clips and sparked. Now when I plug the memory saver in there is no light or beep. I cannot find the obd fuse. I checked the diagram there is no label for that. Now my car key doesn’t work and I have to manually lock them. What should I do? Listen to this man when he says to clip the alligator clips to the plastic it will save you trouble! Especially in my case where I’m not so lucky to have a fuse labeled to the obd port.

[@ryancasing9299]

Obd** not bod

[@ChristopherLum]

I'm sorry to hear that. It sounds like something else shorted and blew a fuse. Have you tried systematically pulling out each fuse and checking is they have blown?

[@ChristopherLum]

@@1010s1-c sorry, I'm not sure what is going on. Good luck 🤞

[@jonathanparkhurst1080]

He sounds like Linus Tech Tips

[@benedictindaa9175]

I like

[@sturben2453]

He must be paid for pushing these memory cables. Just have a spare battery or jumper unit then, remove fuse cover under the driver side dash. You will see a red positive terminal. Pull it out, connect positive cable from spare battery or jumper unit first, then connect negative cable to driver side door bracket. You will have all neccessary power to whole car, radio, trunks etc. NO MEMORY CABLES NEEDED, DO NOT WASTE YOUR MONEY ON IT!!!! Then go and replace your battery.

[@hs4u537]

Think this is useless really they should have invented it with a self power supply! Or I'll need 3 12v battery!! One is the battery I want to swap out 2nd is for the power saver and 3rd a new 12v battery that replaces the main battery! I guess this is only useful for some car maintenance that requires you to remove main battery if located in engine bay

[@pecv4776]

No entiendo ni mierda

[@cfunkful]

so unnecessary

[@b.w.2016]

i'm glad i didn't buy this one.

[@miroslavvitek8960]

Too much chatter

[@goddessmanbo5374]

I’m trying to figure out what reason we would need to get this battery saver and I agree with you to much talking

[@curse_illusionss2871]

@@goddessmanbo5374 best way I can put it is that it’s designed to save the Vehicle’s preset such as radios clocks even from your vehicle’s correct air fuel ratio certain cars when you disconnect the battery they begin to run horrible due to the fact that the pcm has to relearn it’s presets to get the car how it used to be leading to it idling poorly

[@ghost6500]

why people with horrible voice make videos?

[@putsaler13]

Just what will happen if I disconnect the battery from car without any electric to the car?

[@bbmak0]

what about those AC to DC cigarette Converter. Is that something easier to use?

[@smc9764]

Should have a diode on the positive side to allow electricity to flow in only one direction.

[@Eli_is_a_Lauver]

I liked your explanation 🙂 !!!