I, a middle-aged woman, just installed the 12v battary on our 2yar Tesla 3 following this video. Feels so proud.

My Model 3 battery died without any warning, leaving me stuck in my rural hometown. Tesla said that I was out-of-reach of mobile service until the second week of September, and that I'd have to have the car towed to their service center 90 miles away at my expense to have it replaced sooner. I decided instead to order this replacement, since, even if I was out of commission for a couple days, at least it would be shipped to the door. Less than 24 hours later, and I just finished the install with the help of this video, and everything is back up and running.

I purchased an Ohmmu battery for my Model 3 and Sean came to my house and installed it. He's extremely knowledgeable and friendly. I could have talked to him for hours about electric cars. You can’t ask for better customer service. Thanks again Sean.

So many youtubers who make step by step videos leave out some important steps. Not here. Well done detailing each step for us.

The written instructions (Tesla/Ohmmu Tech Note) differ slightly. The Tech Note tells you to disconnect the 12v battery *before* the high voltage, then disconnect high voltage then wait 2 minutes, then specifically NOT re-connect the 12v battery until the high voltage is re-connected. It warns that re-connecting the 12v battery before the high voltage can lead to over discharge issues (though it sounds strange as nobody would do this for an extended period). I think both instructions are safe and work. I followed the Tech Note but this video was still valuable to give confidence about the procedure. It would be good if Ohmmu could correct either the Tech Note or this Video to avoid uncertainty for other customers. I highly recommend the Ohmmu replacement battery for weight savings and longevity alone. The potential benefits of more power with less sag are a bonus too. A replacement Tesla battery with labour costs at least half and may have to be replaced twice in the same 4 year warranty time of the Ohmmu battery. This is a positive upgrade whichever way you look at it, for the features or just to avoid having to replace the lead acid battery. It will most likely return more than the investment over the lifetime of the car, as LiFePO4 batteries should last that long without any replacement.

I had to buy a Tesla battery today because my car literally died outta no where, but your video was extremely helpful My model 3 is at 144k miles and this was my first 12v. Might I suggest adding something on how to open the hood when the battery is completely dead? In case anyone is wondering, pop the tow hook cover off, grab the wires connected to it, and hit em with a 9v battery (positive wire is marked red, and is longer).

Man i wish i had this video last Sunday lol. The harness had me scratching my head for an hour.

Thanks. Your tutorial was super simple to follow, and everything was done in less than 30 minutes work. You saved me the 2 work day plus weekend wait for Tesla to come do it. You rock!😊

Great step by step instruction.

Not sure how long the OEM batteries last but I've saved this video towards battery replacement when the time comes. Excellent video, thank you!

Had mine a year and a month and no issues. Will be getting one for the model Y. Thanks.

Used this tutorial to replace my M3 battery. Worked great. One thing that was different was that as soon as I put on the negative side the car fully booted back up

Great vid, just bought a new Model Y so not planning on replacing my battery for a few years, but I did ask my local SC how much it would cost and they said $112 ($85 for OEM battery and $26.25 Mobil service labor total is $111.25). That’s cheaper than I anticipated and it’s done in your own garage.

That's not the correct power down procedure you can damage modules in that way. Granted it's a very small risk but still not worth it. 1. Lower windows and power off from screen 2. Disconnected the neg cable on the battery 3. THEN disconnect the LV connector under the back seat. You can now replace the battery however once you do, DO NOT CONNECT the neg cable yet. Now powering back up is in reverse. Connect the LV connector then finally connect the neg cable Other then that it's a very informative video

Thank you. I wish I could have bought one of your batteries but I have a road trip coming up. You saved that trip btw so I really appreciate you showing me how to swap my battery.

I had a technician put it in $123. Thank you very much.

Thank you for the great video. I just installed your battery in my P3D; simple install and one can really notice the weight difference between the OEM battery and this battery 😀

yeah, that Ohmmu battery is a win win to replace the BP battery. thank you for more explaining about dc-12.dc converter I would love to replace the original battery right after 3years/36k miles.

Really awesome video, Sean! I can't wait to have this better quality battery in my Model 3. Thank you all so much.

What great video! How much savings to the owner vs being done by Tesla. I would think the ranger would do this with a home visit. I'm really impressed by the angle Tesla designed into the metal caps for plus and negative terminals.

Battery works great. Just for peace of mind of anyone else doing this. your car still makes noise after disconnecting high voltage. Sort of a fan/pump type of sound my guess to keep the battery cool. I thought I messed up cause I thought it be dead quiet then I listened closely to this video and you can hear it

Nice video. Just got an alert on my 2018 Model 3 to replace the 12V battery.

These are good instructions but you should say to wait 2 minutes minimum between turning off the high voltage connection and the other steps.

I don’t even have a Tesla. But it was a great video

Personally, the very first thing would be to remove the Negative battery post clamp. Then, even if you were to touch the tie down bracket across positive and the vehicle body, there would be NO arcing since there is no longer a way to complete the circuit through the battery. The Negative post clamp should also be the very last thing attached, for the very same reasons.

Thanks for the great video with detail! I've just purchased one and replaced the bad OEM battery.

Just replaced my OEM battery with the Ohmmu lithium for 2019 Mod3 SR+. Everything went smoothly. Error messages gone. Will road test later. Thanks!

Great video with lots of helpful information! I am thinking about performing the swap on my 2021 M3. Could you elaborate whether the swap or work on the 12v battery will affect any of Tesla's warranties?

Ordered M3 battery on Monday, arrived on Wednesday, installed in less than 30 minutes. Excellent video. Thanks.

You guys need to make a installation video for the Model Y on your website. I looked under there rear seat the high voltage cut off is not located there on the Model Y.

Nice video! Gotta love that lithium! 🙂

I changed the 12v battery just as you had shown. The car now works. However, the warning message to replace the battery soon did not go away. I rebooted the car twice. Now what?

Costco won't tell you they have Tesla battery, but the Interstate 51R group dropped right into my 2019 M3LR

Excellent video!

Just ordered two for the two model 3's we have, I love that you use 10mm metric lol

I did one extra step. I gaffer taped the gas tube to the side of the battery just so I don’t hear it knocking around when driving

My Model 3 is showing “asleep” and neither the App or the key card won’t unlock the doors…I’ve been trying to figure out what’s going on and some have said it’s the 12v battery needing replacement. I got the frunk open and access to the 12v battery, but the DIY’s are showing the car has to be off and windows down to replace the 12v battery. How do I do that if the car is off and still locked? The jumper cables won’t unlock the doors either even when I connect it thru the old 12v battery.

How does Tesla see the new Lithium Batterie under Service Info. Actually my M3 from 2019 shows a „lead-acid“ Battery which is installed. Do i have to change it via Setup in Service Mode??

Followed each step by step but after about a month 12 V replacement prompts on MCU returned. Attempted to contact company still waiting return call. Please help.

Very well done, will be getting one of these for my Model X after I drive out of the warranty.

Excellent presentation !

Well done 👍🏻

I have a 2021 M3 with a LHP battery. I keep hearing that if you have a LHP battery you can only replace with another LHP. Tesla owners are reporting complications with swapping out to a lithium. Any comments..?

Thank you ... this info is hard to find !

Tesla told me I can't install a Lithium battery for the 12v system, because of "Codebase" reasons, citing that there would be neccesitations for multiple variations of code-base per vehicle to support such things and that my 2021 model 3 SR+ would never be able to have a 12v lithium battery... Any opinions on this ??

In the video the vent tube is left loose, so just remember to connect vent tube to the new battery.

I just wish these things were in stock, now that I need one. I should have bought one sooner and just stored it.

I will be ordering mine in June, great video and huge thanks.

Where do you buy that wrench?

Wow! Great video and a lot of information. Thanks.

Here’s the situation for most people...your Model 3 12V battery is going bad, the car tells you it is going bad and you have time to call Tesla service. Tesla comes to your house a couple days later and installs the new battery, free, under warrantee. If you’re lucky even the next time the 12V fails you are still inside the 8 year warrantee. After that one might want to consider alternative batteries, not before (and not before 2025 for any Model 3, first released in 2017). If you’re too far for mobile service, you can always take a little road trip.

Replacing battery after warranty

I have a 2018 dual-motor long-range model 3. please tell me if the OEM battery is or is not an lithium ion type??? Also would like to know what is the life range of the OEM battery on model 3? My 12 V battery just died, two hours away from my house, with no prior warning on the display !

It doesn't make any difference on the Model 3 for High Bass, because everything in the M3 is mostly run off of the dc dc converter which supplies up to 2000W, but if you draw too much amps from any circuit the e-fuse will shut down the dc dc, regardless if the 12v battery could have supplied it.

Hello. I have a question. What about charging Lithium battery. As I know there is different type of chargers for different type of batteries. Is tesla Model y charger is ok with Lithium battery? And will I see in car spec that it is now Lithium and not lead-acid.

Great instructions! I just replaced my M3 battery and it took less than 20 minutes!

Do we need to purchase the 12V batteries to Tesla specifically? Or is a standard one?

Fantastic video! Thanks for sharing.

Have you had any problems yet like Tesla is having since including lithium 12v batteries from the factory?

This battery sounds awesome. Any holiday cheer with a discount code?

Great info... thank you!

Due to the potential for arcing, is it a "must do" to wear gloves like you have on during the video? Are those gloves specifically designed to guard against electric shocks?

Really great video!

Very well instructed. Step by step.

Great video!!! Thank you so much 😊

How do you replace the 12v battery when car is dead and you cannot open the car? Hood is open by way of jumping bumper access

Have you guys tried making a higher voltage battery and see if that works with this 12v error alert issue?

Will doing this help with clearing a "VCFRONT a196 - Low voltage battery disconnected" warning code?

How long do they last?

Hi,🤣 dieses Wort bedeutet in der deutschen Sprache soviel wie Ende, Meditationskuh oder Meditations...😊. Meine Frage wäre ob und wo ich so ein TShirt kaufen kann. M.f.G. Petra Berger vormals Platzer und vormals Nittel

Hi. I followed your steps. Replaced the battery. But now I can't start the car！

It looks much easier and easy on your back if you stay in front while lifting and replacing the battery.

Thank you so much for this video!

But... what is this classic 12V battery needed for in the electric car? :-0

How do we open door to get under the sear to turn off high voltage if the 12V battery goes out?

Would live to get these for my Model 3 Racecar and my new Model Y

Is it supposed to make a weird humming noise after removing high volt battery connection?

So what’s the purpose of that 12v battery on a Tesla? Is it for the wireless chargers, speakers?

Can you replace a lead acid 12V battery with the Li Iron Phosphate batter? Does the car care?

Nice step by step. What year was that Model 3 you did this on? Thank you.

Is there a risk of losing any settings while the power is disconnected?

Does replacing OEM 12v battery with this battery void factory warranty?

Is there any coding needed or is it really this easy?

That intake definitely needs a filter

I installed one of these in my 2019 M3. At first it seemed great. Then it started to give me the error. After the 3rd dime in 2 months I pulled the Ohmmu battery and bought a new one from Tesla. Yes, you can reset it, but that profess is NOT simple (anyone care to download a binary file on your phone and move it to to the car?), but since its my wife’s daily drive that was not an acceptable situation. Also, the chat link they have on their website is not manned during the day in the US. If anyone would like it, its available for free. You need to pick it up or meet me somewhere in the Vail valley. Otherwise, its going to the recycle center the next time I go there. What a waste of money.

Very informative. Thank you.

What did you do with the vent tube? Was it plugged in again? Or left to dangle?

In a new 2022 Model 3, it's a 12v battery with about 7000 mah, correct? If you leave several things charging in it over night, does the 12v battery go dead or does the main battery automatically start charging it when it gets low?

So the spacers come with the new battery?

What is the point or benefit of swapping to a lithium 12V battery?

If you need to disconnect things in the penthouse, should you update/delete the other video from last year that just shows a soft shutdown and nothing about the penthouse? I'd love to get one but I imagine shipping to Ireland is pricey? Or do you have a European dealer?

Wow, changing the 12v battery requires an Up, Up, Down, Down, Left, Right, Left, Right, Select, Start Code. Instead of just opening the hood and swapping the battery.

My Owners Manual says my 12v battery is lithium ion (2023). Is this a lie?

I see only model Y battery is available at the time and model 3 is out of stock. is there any difference? can the model y battery work for the 3 and vise versa?

How do I find someone to install this battery?

Do these batteries have low temp cut off?

Nice video. How about the cost of these Litium batteries compared to the AGM? Is it still worth it? I mean the weight saving has gone lost in the last months at home in this corona time.🤣

Is there a Canadian distributor?

How often do you need to swap the 12 v battery?

Does this apply to Model Y?