Model 3 12v battery dead

[Rice&Curry]

I got the warning a couple months back, and called for service. They made me an appointment to have the battery taken care of, under warranty.

you are the chosen lucky one!

 

[Blue Express]

I just had my 12V battery replaced by mobile service under warranty despite not yet having issue with the battery before my warranty ran out on my 2018 Model 3.

 

[SylvainG]

Are you saying Tesla proactively replaced your functioning battery before your warranty expired? What did you tell them?

 

[iwannam3]

Won't the car with all its technology warn you ahead of time that the battery is dying and will need to be replaced soon? My $50 UPS does that, surely my Tesla can do it too?

No,

 

[mckemie]

There are many threads on here. Perhaps you could view or search before pasting? If you had, you would have known to just call the service number, report your car as inoperative, and there would have been a tow-truck there in an hour or two, with the battery replaced shortly after it arrived at the service center.

Yes. There is so much that needed information is hidden in the noise. I am in the process of dealing with the problem now and seeking how to start a car that now has good 12v but remains dead. A request for service through the app, resulted in a mobile service appointment. About 10 days out. Searches have revealed how to access the battery when the car is dead. And how to replace the battery. I have not learned how to bring the car back to life.'

 

[mattnis]

LOVE TESLA but it shakes me a little when I use the car for 1000+ mile road trips knowing that I could be stuck literally in death valley without any kind of major warning, I was hoping to use this post so people can say what to look out for/warning signs

Literally, just get a $50 lithium ion jump start battery to keep in the trunk. Yes, you shouldn’t need it, but it’s extremely super easy low cost low complexity, never get stranded solution,

 

[mattnis]

Just had my 2018 flatbedded off today. Spontaneous death of 12V, ironically, about 2 hrs after mobile tech fixed charge port. No warning...

I keep a small 12v lithium ion jump start battery in all cars. It’s super easy and never know when you would need it for yourself or do someone else.

 

[SylvainG]

Literally, just get a $50 lithium ion jump start battery to keep in the trunk. Yes, you shouldn’t need it, but it’s extremely super easy low cost low complexity, never get stranded solution,

Once 'jump started', will it keep running off a dead 12V battery as long as it doesn't go back to sleep?

 

[android04]

Once 'jump started', will it keep running off a dead 12V battery as long as it doesn't go back to sleep?

Yes, unless the 12v battery is in a bad state (multiple shorted cells) and the DC to DC converter shuts off to protect the electronics. Then you will have to replace the 12v battery.

 

[N54TT]

Yes, unless the 12v battery is in a bad state (multiple shorted cells) and the DC to DC converter shuts off to protect the electronics. Then you will have to replace the 12v battery.

the thought for this situation is to just disconnect the shorted 12v battery….to prevent the dc to dc from protection shut down...especially in the case where trying to jump the car with a shorted 12v.…prevents the contactors from closing.

 

[android04]

the thought for this situation is to just disconnect the shorted 12v battery….to prevent the dc to dc from protection shut down...especially in the case where trying to jump the car with a shorted 12v.…prevents the contactors from closing.

That's what I would do, just making sure that the positive 12v cable doesn't get shorted to ground. I can use my jump starter as a battery (by putting it in Boost Mode) just in case the car turns on but doesn't let me put it in drive without a 12v battery connected.

 

[SylvainG]

The battery also acts like a huge capacitor, filtering the 12V power line of any spikes. If you just remove it, it could be bad for the electronics.

 

[iwannam3]

The battery also acts like a huge capacitor, filtering the 12V power line of any spikes. If you just remove it, it could be bad for the electronics.

I would think the DC/DC converter would throw a bunch of error codes just like it did when the BMS changed and the Ohmuu battery BMS had to be modified.

 

[sodakar]

Literally, just get a $50 lithium ion jump start battery to keep in the trunk. Yes, you shouldn’t need it, but it’s extremely super easy low cost low complexity, never get stranded solution,

I'd vote for the frunk over the trunk. I, too, had my Li-Ion jump start pack in the trunk, and kicked myself for not thinking this through. When my 12V died last week, it rendered all doors/windows + frunk/trunk useless, making the Li-ion jump start pack inaccessible. I could only get as far as opening the frunk using a 9V battery on the tow hook leads, but despite having the 12V battery in front of me, I had no means to jump it myself. Doh.

 

[deadlion]

Last Thu was our turn. My son jumped in to drive to school and it died in the garage as soon as he closed the drivers door. I was about to try the 9V frunk pop and then jumpstart but thought I'd give Roadside Service a try via the app. As we waited for a reply my wife reported a horrible smell of sewage in the garage after the school run - 12v battery death for sure. The orig battery lasted just over 3 years - just over 20k miles.

Within a short 35 min the tow truck arrived. The tech/driver had it jumped and on the truck in 20 min. Received notice of job done via the app in the evening and picked it up - no touch.

Looking forward to a future where we can buy batteries off the shelf (or when lithium's get the OEM replacement thumbs up). Purchasing a jumpstarter soon for the frunk.

 

[iwannam3]

Last Thu was our turn. My son jumped in to drive to school and it died in the garage as soon as he closed the drivers door. I was about to try the 9V frunk pop and then jumpstart but thought I'd give Roadside Service a try via the app. As we waited for a reply my wife reported a horrible smell of sewage in the garage after the school run - 12v battery death for sure. The orig battery lasted just over 3 years - just over 20k miles.

Within a short 35 min the tow truck arrived. The tech/driver had it jumped and on the truck in 20 min. Received notice of job done via the app in the evening and picked it up - no touch.

Looking forward to a future where we can buy batteries off the shelf (or when lithium's get the OEM replacement thumbs up). Purchasing a jumpstarter soon for the frunk.

$85 across the counter at Tesla, no core charge.

 

[Rsamper]

Just wondering if I could gather stories of what happened with owners and what happened so that we could gain insight with this issue, I've been looking around the internet but wanted to condense stories here...

Personally had a warning the day before, I scheduled the service for 5 days from then (earliest available) the next day the car was completely dead, when I opened the door the windows started rolling down very slowly but the cars screen did not work, even the button to open the door was unresponsive. The car was completely inoperable to the point they could not even put it in neutral to move to tow the car. A quick internet search showed that it was probably the 12 volt battery which Tesla confirmed and replaced under warranty.

I want to know if this should worry me...I've taken road trips with this car and in some cases these places were isolated, what worries me is that this might happen again and I want to be able to see it before it does. In my case I had a warning the day before then the next day the car was completely inoperable.

How are you able to tow the car if it is dead, and locked? I was able to open the frunk with a 9 volt battery but couldn’t jump start the 12 volt battery. Thus I am concern how I get the car towed to a Tesla service center

 

[android04]

How did you try to jump start the 12v battery? Keep in mind that the two wires that are behind the tow hook cover are only to pop open the frunk, they don't connect directly to the 12v battery. You have to jump start the 12v by connecting directly to it (it's under the removeable plastic trim at the rear end of the frunk. If the 12v battery has shorted cells, then jump starting the car with it still connected might not work. In your situation, I would just disconnect the 12v battery and jump start the car directly (I'm not under warranty and can replace the battery myself with one from an auto parts store). Or if I was close to an auto parts store, I would walk or get a ride there and buy a replacement 12v battery. If you are under warranty, just let Tesla and the tow provider worry about towing the car.

 

[N54TT]

How are you able to tow the car if it is dead, and locked? I was able to open the frunk with a 9 volt battery but couldn’t jump start the 12 volt battery. Thus I am concern how I get the car towed to a Tesla service center

How did you try to jumpstart? What did you use? Did disconnect the dead battery? Did have the rotten egg smell?
Every post I’ve seen about people not being able to jump start their car, didn’t disconnect the affected battery. I agree with @android04 that if the battery is shorted there is something going on that doesn’t let you jump the car while the shorted battery is still connected. Disconnecting it and applying a sufficient 12v source should allow you to jumpstart and drive as long as you want. As long as you don’t let the car sleep and there isn’t anything wrong with your dc-dc converter.

 

[iwannam3]

How did you try to jump start the 12v battery? Keep in mind that the two wires that are behind the tow hook cover are only to pop open the frunk, they don't connect directly to the 12v battery. You have to jump start the 12v by connecting directly to it (it's under the removeable plastic trim at the rear end of the frunk. If the 12v battery has shorted cells, then jump starting the car with it still connected might not work. In your situation, I would just disconnect the 12v battery and jump start the car directly (I'm not under warranty and can replace the battery myself with one from an auto parts store). Or if I was close to an auto parts store, I would walk or get a ride there and buy a replacement 12v battery. If you are under warranty, just let Tesla and the tow provider worry about towing the car.

Have you looked at an autoparts store? I haven't been able to have on pop up on their online catalog. $85 over the counter at Tesla, no core.