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12V Battery Just Died - Total battery failure

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My 2018 Model 3 LR with 10k miles just had a 12v battery failure and it had to be towed to Tesla. It was so dead that Tesla couldn't confirm the issue remotely and therefore could not dispatch the mobile service vehicle. The car was parked in the driveway so the tow truck operator had get it in towing mode by attaching a battery device to wires behind the tow hook cover then opening the frunk to get his battery attached to the car battery. It worked for awhile but eventually towing mode stopped right at the flatbed ramp. So we attached my 12 amp battery charger to the car battery but that didn't work either so he dragged the car the rest of the way onto the flatbed with the help of liquid dish washing soap. Oh, then the right hand front window went down so we had to cover it with a trash bag using 200 mph racer tape I had on hand. (I used to race cars) I needed to do this because I live in Florida and we have showers this time of the year. The car was getting towed to Tesla's new service center in Fort Myers which is only 30 miles away. Otherwise it would have to go 105 miles to the east coast or the the same distance to Sarasota. What a pain the rear end. I have a 2017 Model S 100D with 12k miles and I'm wondering if I should change the 12v battery to be safe. Any thoughts please.
Yes you should get a lithium 12V battery. Read many posts here about Ohmmu. 12V lead batteries do not last long in Teslas in hot climates. Arizona is hotter than Florida but I’m sure you suffer the same problems. Just get a lithium 12V and be done with ugly stranding, towing, etc. situations. At least you were at home for this one.
 
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Bleh, so I think the 12 volt battery died on my wife’s model 3. Car won’t connect to the app, drivers side doors won’t upper, passenger sides did…but groaned as they took the last bit of juice from the battery I think…one of the windows is down and won’t roll up…touchscreen not working…bleh…can’t access the frunk…

can’t schedule service since I can’t access the app for the vehicle and can’t call anyone at Tesla to schedule service…guess I just have to wait till tomorrow, unless anyone has any ideas…need to cover up the windows I. Case it rains, at least the car is at hime in the driveway and not somewhere else…
 
On the front bumper, there’s a disk about an inch and a half in diameter. The manual describes how to attach a battery (even a 9v battery) to the wires underneath this disk, which will pop open the frunk. You can then put a battery charger on the 12v battery, and the car will probably instantly spring to life and start charging the 12v by itself. I’d do that tomorrow, and as soon as the car wakes up, drive to the service center. Of course, if you have windows down maybe do it today so you can roll the windows up.
 
On the front bumper, there’s a disk about an inch and a half in diameter. The manual describes how to attach a battery (even a 9v battery) to the wires underneath this disk, which will pop open the frunk. You can then put a battery charger on the 12v battery, and the car will probably instantly spring to life and start charging the 12v by itself. I’d do that tomorrow, and as soon as the car wakes up, drive to the service center. Of course, if you have windows down maybe do it today so you can roll the windows up.
Thanks, I've been googling and looking up things and have a game plan to go to autozone and buy a Duralast Gold ETX9 Group BTX9 AGM battery. They say it will work in a model 3 and apparently the current battery in the model 3 is an AGM battery. One I have that I will try and pop open the frunk and then follow the steps I saw online for replacing the battery (the steps I saw also mention disconnecting the main batter by accessing something underneath the rear passenger side seat).
 
Thanks, I've been googling and looking up things and have a game plan to go to autozone and buy a Duralast Gold ETX9 Group BTX9 AGM battery. They say it will work in a model 3 and apparently the current battery in the model 3 is an AGM battery. One I have that I will try and pop open the frunk and then follow the steps I saw online for replacing the battery (the steps I saw also mention disconnecting the main batter by accessing something underneath the rear passenger side seat).
I am virtually positive the current battery in a model 3 isnt a AGM, since it cost less than $100 when you buy it from tesla.

There is a long thread on model 3 and 12 volt, that you can find here:

 
Thanks, I've been googling and looking up things and have a game plan to go to autozone and buy a Duralast Gold ETX9 Group BTX9 AGM battery. They say it will work in a model 3 and apparently the current battery in the model 3 is an AGM battery. One I have that I will try and pop open the frunk and then follow the steps I saw online for replacing the battery (the steps I saw also mention disconnecting the main batter by accessing something underneath the rear passenger side seat).
Nvm, that battery does not work…checking with Tesla first thing in the morning
 
They say it will work in a model 3 and apparently the current battery in the model 3 is an AGM battery.
As @jjrandorin said, it is not AGM - there is a thread about this which has determined this as definitively as possible (battery manufacturer catalog).

The best option is the Tesla replacement (since it is either free, or $85 out of warranty (plus $40 install cost if you do not do it)) but there are stories about them having supply chain problems right now, with the reopening “reverse-toilet-paper“ shortages.

51R is the right group type, as I recall from those threads, if you want to replace it with a non-OEM type, but it will be about $200 probably.

Let us know whether Tesla had the replacement. Would be nice to know.
 
Picking up a battery from the tesla service center this afternoon ($85).
The car is out of warranty then? Or you just don’t want to bother with Mobile Service or Service Center?

Assuming the latter:
If available, Mobile Service is nice because they will also do any outstanding warranty work on the car that needs doing if it can be done by Mobile…

I understand the 12V being dead could make this difficult, but if you could get the car going again with the method described above (and you are comfortable with that) they can probably remotely diagnose it without having to send a truck for it and all that hassle.
 
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Curious (for age of 12V) - is it out of warranty based on age or mileage? And how old is the car?
Its a 2018 model 3 that I got in August in 2018 (I think). I have over 50,000 miles. I might have had the battery already replaced once (I can't access the app so I can't see my service history, and I don't remember if it was this model 3 or one I just sold) so maybe the battery might still be under some sort of warranty.
 
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Car is working fine with new battery…wish the app would have given us some advance warning….based on the alerts the vehicle started having errors like at 6:30 in the morning but nothing was sent to us via the app. My wife had loaded our kids into the car (which was hot since it wasn’t cooling) like at 1 PM and then got locked inside when the battery full failed…in her panic she didn’t remember the emergency door handles and eventually was able to call me and I told her how to get out. She could have very easily loaded the kids in and then not been able to get into the car. Altogether she was stuck in the car for like 4 minutes (it was probably 130 degrees in the car)
 
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Car is working fine with new battery…wish the app would have given us some advance warning….based on the alerts the vehicle started having errors like at 6:30 in the morning but nothing was sent to us via the app. My wife had loaded our kids into the car (which was hot since it wasn’t cooling) like at 1 PM and then got locked inside when the battery full failed…in her panic she didn’t remember the emergency door handles and eventually was able to call me and I told her how to get out. She could have very easily loaded the kids in and then not been able to get into the car. Altogether she was stuck in the car for like 4 minutes (it was probably 130 degrees in the car)
This is pretty disappointing that they do not have better detection of this sort of failure.

Was the battery showing any signs of distress (swollen, etc.)? No warnings showed on the screen at all? No foreshadowing with somewhat slow mirror opening with contactors open or anything?

Just seems like a low capacity or internally shorted 12V should be pretty easy to detect with all the information at Tesla’s disposal. Though maybe a short could develop very quickly, you would think the car would just still have time to close the contactors and stay fixed in idle mode and throw a lot of warnings until the battery was replaced.

Going on a long road trip and it would be nice to know my 12V is in good shape. Replacing it is questionable, because then I could end up with infant mortality!
 
This is pretty disappointing that they do not have better detection of this sort of failure.

Was the battery showing any signs of distress (swollen, etc.)? No warnings showed on the screen at all? No foreshadowing with somewhat slow mirror opening with contactors open or anything?

Just seems like a low capacity or internally shorted 12V should be pretty easy to detect with all the information at Tesla’s disposal. Though maybe a short could develop very quickly, you would think the car would just still have time to close the contactors and stay fixed in idle mode and throw a lot of warnings until the battery was replaced.

Going on a long road trip and it would be nice to know my 12V is in good shape. Replacing it is questionable, because then I could end up with infant mortality!
It’s possible they the horn sounded a bit quieter a dees days ago when the car would lock and honk when you walked away.
 
I’ve seen enough reports of 12V battery failures without warning that I keep a little A23 battery in the front bumper to pop the frunk, and then one of these in the frunk to jump the battery:
Yeah I definitely think this would be good; I just worry about it setting my car on fire. And then I can’t keep it at home, because it might set my house on fire. Decisions!

The A23 is a good idea. Do you just store it in the hole for the wires to open the trunk, or somewhere else? How do you secure it and prevent it from bouncing around?