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12V Battery Failure Experience

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Walked out to my vehicle after work today to find it totally unresponsive with a blank screen. The windows and locks worked (extremely lethargically) but the phone app indicated that there was no connection. Attempts at restarting did not work. Luckily I had a jump starter battery pack in my trunk from a recent ICE jump for a friend, which also happened to be mostly charged.

I followed directions for jump starting from the user manual and the jump pack but neither resulted in positive feedback except that the jump pack was draining. I reluctantly called roadside assistance which sent a tow truck out and said it would be at least an hour. Great.

I walked back into my office building to wash my hands and cool off and then walked back out to my vehicle to troubleshoot some more. At this point about 20 minutes had passed since I first got to the unresponsive car. I noticed when walking back out that my phone connected to the vehicle. I could remotely unlock/lock but could not start the AC (received "could not start AC" error on the app). Approaching the car I could hear the normal humming which indicated that the AC was attempting to start up. I peered through he window and the screen was on, sweet! There was an error indicating that the 12V battery should be replaced soon.

I counted my blessings and figured I would risk the drive home since the 12V should cycle and promptly called the tow company dispatched by roadside assistance to cancelled. I got home safely and experienced no issues during the drive home.

It wasn't until I pulled into my garage that I started thinking that this 12V battery may not be easily replaceable. Some quick googling indeed confirmed my suspicions that the battery is non-standard. Tried calling the service center which robo-informs me the only way to schedule is through the app. Quickest appointment is 7 days from now. Car is once again unresponsive in my garage.

Anyone have any tips on how to get Tesla to do this very simple thing in a timely fashion? It's a little ridiculous that I could have had faster service by accepting a tow. Not being able use my vehicle for a week due to a faulty 1.5 year old 12V battery is unacceptable.
 
You did not mention any self questioning as to the cause of this. Do you have any non-Tesla accessories in/attached to your car? A dashcam connected directly to the battery maybe?

What can you do? Get it started again and drive to the SC and ask them for help. Hard to turn down someone at your door.

The app does not prioritize request for help. So, submit the work request via the app, and show up as soon as you can and be nice. Be very nice. Take donuts if you can. And ask for help, "please". I believe you will be surprised by the outcome.
 
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I do not have any non-Tesla accessories in or attached to my vehicle, aside from a USB thumb drive. Should have mentioned I was planning on going to the SC today regardless, if the car starts anyways.

This morning I received a text that a mobile tech "may" be able to fit me in between appointments today, but no mention of time and no response to my acceptance as of an hour ago. Kind of hard to plan your day around these things.

I'm sure it will get solved today one way or another and I'll post an update for others who may experience this in the coming months. Just a frustrating waste of PTO for a problem that's solvable in about 20 minutes with an ICE vehicle.
 
Good. Good too that they may be able to squeeze you in. They will find you, they come to the car. They will call you to locate you. You're right, its going to work out.

The reason I asked about any non-Tesla stuff, is it bypasses the battery management system that protects the battery by monitoring drain. Its a bit early for your 3's battery to be failing. I suspect you already know that.

Good luck. :)
 
Not being able use my vehicle for a week due to a faulty 1.5 year old 12V battery is unacceptable.

You are the judge and the jury as to what is acceptable. Sell the car then.

Tesla has lots of cars on the road whose batteries are fine. You fault them for using a non-standard battery, but that is just absurd. ICE cars can be recalled and have issues as well.
 
Is it most likely just a faulty battery?
How much life are we supposed to get out of them? I assume their strength is tested when the car goes in for service?

Let us know how you make out, and I'm sorry for what you're going through. You have a right to be furious.
 
It is most likely just a faulty battery. If it were just excessive at-rest draw the main battery would be used to recharge it.

I imagine they are 5-10 year batteries, they have a pretty easy life..... living in a relatively constant temperature environment, never having to supply enormous power for 5-10 seconds at a time, probably see less vibration than an ICE battery.
 
You are the judge and the jury as to what is acceptable. Sell the car then.

Tesla has lots of cars on the road whose batteries are fine. You fault them for using a non-standard battery, but that is just absurd. ICE cars can be recalled and have issues as well.
I was faulting the 7 day schedule for simple battery swap, ICE cars do not have that issue lol. I'm not grandstanding about EV's or unique design, just Tesla's service issues. If this problem really did take 7 days to fix you're darn right I would have sold the car.

To update the thread: A mobile tech came out about 2 hours after my initial text and swapped out the battery in 10 minutes flat. Anecdotally he expressed that the 12V batteries in the Model 3 seem to be lasting 18-24 months on avg.

I'm still not happy about the process of setting a random appointment and hoping someone moves it or calls you but I cannot complain about expedience in this particular case. Also I forgot to mention but Tesla texted me a full hour before the SC opened so it ended up taking less time for mobile service than it would have taken me to drive the SC and had service done there.
 
18-24 months??? If that's true it is mind-bogglingly absurd.
There has to be a way to monitor the battery and/or check on its health so we don't get stranded.

18-24 months is just arriving now (or at least in the next six months) for tens of thousands of 3 owners. It should become very clear if that's a real number or not. I'm betting its crap.
 
I went out to my car one morning and it was totally dead. I never got a warning on my screen mentioning a low battery condition. I figured I could hook up my portable battery jumper and drive to the service center for a replacement battery. I couldnt even get the tow hook cover off. It wouldnt budge at all. I left the car alone for a few hours and was lucky enough to pop open the frunk by the app. I connected the portable jumper to the battery hoping to get enough to start the car and drive but it never worked. Tesla sent a tow truck but it was unable to pull my car out of my garage because the car would not go into tow mode. Tesla sent a second tow truck with a special remote controlled device that was able to pick up my car while it was in my garage. It was totally cool to watch because I've never seen one of those before, however I think it would have been a lot more cost effective to send out a mobile tech with a battery. My car was delivered to the service center around 9pm and i got a call that it was ready for pick around 8am the following day. It was really fast service and they paid for me to take a Uber ride to the service center. I was really happy with the service. The worrying part is that the tech told me that I should have been getting warning message on the screen about a week before the battery died. The battery only lasted about 15 months down here in Miami. I think I'll have to put it my calendar for 15 months from now to maybe have them run a test on it. I wish there was some way to see the condition of the 12v battery somewhere on the screen (like a battery meter).

Anyway here is a pic of how they got my car...
 

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I saw these two warnings one night after work. It took about 20-25 mins for the car to power up and become drivable. It functioned just fine for the next week while I waited for my appointment. The service center told me there was a lose connection for the low voltage battery at the battery control module. They replaced the connector and the 12v battery. It has been fine ever since.

My car was about 4 months old and had 3k miles on it when this happened.
 

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18-24 months is just arriving now (or at least in the next six months) for tens of thousands of 3 owners. It should become very clear if that's a real number or not. I'm betting its crap.

Back when the family owned 3 VWs, all within a year or 2 of each other in age, each and everyone of them had a failed battery at so-close-as-not-to-matter the 36mos end of warranty date. IE they failed just after their warranty coverage had expired.

Some batteries are long livers, some not so - not including defective units which die whenever. My folks had an old Oldsmobile that when the battery finally failed, my dad was shocked to realize it was 8 years old.

Will be interesting to see some real stats when the 3's start being more than a year or 2 old.
 
I was walking in my neighborhood yesterday and talked to a neighbor who also had a model 3. The service truck was there replacing the battery. He had no warning messages. I had been through 4 batteries in my wife’s S. Each time I got a warning.
This morning I went to get in my 3 and it was also dead with no warning. I drove it yesterday and it was fine.
Interesting, both us us just updated to the new software, 2020.12.5
I am convinced this is a software issue. DO NOT UPDATE.

John
 
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I was walking in my neighborhood yesterday and talked to a neighbor who also had a model 3. The service truck was there replacing the battery. He had no warning messages. I had been through 4 batteries in my wife’s S. Each time I got a warning.
This morning I went to get in my 3 and it was also dead with no warning. I drove it yesterday and it was fine.
Interesting, both us us just updated to the new software, 2020.12.5
I am convinced this is a software issue. DO NOT UPDATE.

John
What convinces you it's a software related issue?
 
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