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12 Volt battery died yesterday

Gasaraki

Active Member
Oct 21, 2019
1,374
939
Syracuse, NY
No I said ignoring everything and saying its no big deal is how we get to the issues I mentioned. A bumper falling off can be fixed, but its a big deal and ignoring it doesn't fix the issue. The battery issue has been going on for multiple years, lets not pretend it just happened now. Yes I have had issues with other cars, but not crazy stuff like this, not things that are happening and no one is doing anything, further as I mentioned, its the insanity of how it has to be done, towing the car somewhere, waiting multiple days for someone to come to you, that is upsetting me more than anything else. Roadside should come out and change a battery. I've loved cars my whole live, but at a certain point, a car is a car and I'm not a fanboy. My 2004 prius don't have these issues, 16 years old and less issues than the Tesla. My corvette has some major issues, 6 to 7 years in, not 15 months.



 
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beachsideev

Member
May 23, 2020
276
134
usa
To swap out the battery yourself, you definitely do not need to disconnect the high voltage battery pack.

Is the dc/dc converter that charges the 12v battery still operational? I could see a scenario where you disconnect the 12v battery but the dc/dc converter is still outputting 12v. If the positive lead were to touch the body you would have a short which could damage things. Shutting off the hv battery should eliminate this scenario.

ice cars don't have this issue unless you are changing the battery while the engine is running. who is really going to do that?
 

MarsOrBust

Member
Sep 25, 2020
433
245
Kepler-22b
Looks like it was my turn this morning. 12 Volt battery dead with no warning. Had to uber to work. Meeting road ranger later today
to take care of it. Batter is 18 months old. Will update later and see how it goes.
 
Had mine fixed this morning, it took 15 minutes, half of which was me shooting the breeze with the ranger. I watched so I could DIY it next time. He did mention disconnecting the HV battery if the 12V wasn’t completely dead, but I forgot to ask how to do that.

There’s really only one thing that makes this more inconvenient than an ICE 12V failure: you can’t open the doors from outside since they’re electrically actuated. That could be a problem. Unless of course your windows are down.
 

GPinzone

Member
Sep 3, 2018
316
168
Ronkonkoma, NY
I just walked into Napa auto parts and got one off the shelf there. Took about three minutes.

To swap out the battery yourself, you definitely do not need to disconnect the high voltage battery pack. The 12 V battery in the Tesla is no different than the 12 V system in any other ICE car. You need a 10 mm socket and about 10 minutes to do it.

To all the people crying about dead batteries: invest $10 in socket set, or a AAA membership. Seriously.

Can you tell us exactly which battery you bought?
 

vickh

Active Member
Dec 16, 2018
3,062
471
az
Had mine fixed this morning, it took 15 minutes, half of which was me shooting the breeze with the ranger. I watched so I could DIY it next time. He did mention disconnecting the HV battery if the 12V wasn’t completely dead, but I forgot to ask how to do that.

There’s really only one thing that makes this more inconvenient than an ICE 12V failure: you can’t open the doors from outside since they’re electrically actuated. That could be a problem. Unless of course your windows are down.

did the windows auto go down??
 

vickh

Active Member
Dec 16, 2018
3,062
471
az
I just walked into Napa auto parts and got one off the shelf there. Took about three minutes.

To swap out the battery yourself, you definitely do not need to disconnect the high voltage battery pack. The 12 V battery in the Tesla is no different than the 12 V system in any other ICE car. You need a 10 mm socket and about 10 minutes to do it.

To all the people crying about dead batteries: invest $10 in socket set, or a AAA membership. Seriously.

Have AAA for my other ICE car. Anyone here use AAA successfully?? (they don't have Tesla listed online)
 

MarsOrBust

Member
Sep 25, 2020
433
245
Kepler-22b
It took him 30 min to get mine done. He did disconnect the HV battery, told me the same thing if battery is totally dead or if something wrong with the 12V battery you can do serious damage to the system. He always disconnects it just in case. It seems pretty easy.
He lowered the drivers window all the way down and the rear right passenger window all the way down. Not sure why. Then he popped the rear right seat up and there is the HV jack. Unplugged it, did a battery swap then put it all back together.

Everything was back to normal again. I told hime it was less than 2 years old and he was not surprised. Guess I will just change it every 17 months just in case.
 
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Margaritaboy

Member
Sep 15, 2019
93
141
Northern California
Is the dc/dc converter that charges the 12v battery still operational? I could see a scenario where you disconnect

Per the service manual, the proper way to do it is to disconnect the 12 V battery, then disconnect the DC to DC converter which is under the backseat. It outputs 12 V, so you’re not really disconnecting anything high-voltage.

I have replaced the battery both the proper way, and also the improper way. Nothing bad happened either way, but if you want to do it by the book then disconnect battery and DC DC converter.
 
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vickh

Active Member
Dec 16, 2018
3,062
471
az
Not totally sure what you mean, but one of the windows (I forget which) did roll down on its own at some point while we were trying to figure out what was happening. Are you saying it does that on purpose to keep you from getting locked out of the car? Pretty smart if so.

yes. it does that on purpose to keep you from getting locked out of the car. Also that means we can keep a jumper in the car and get to it.
 
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Gasaraki

Active Member
Oct 21, 2019
1,374
939
Syracuse, NY
Not totally sure what you mean, but one of the windows (I forget which) did roll down on its own at some point while we were trying to figure out what was happening. Are you saying it does that on purpose to keep you from getting locked out of the car? Pretty smart if so.

OK, I want to verify if this is really the case. When the battery dies, the last thing it does is roll down a window so I can open the door.
 

iwannam3

Member
Aug 8, 2016
898
1,268
Washington
Just picked up an $85 battery at Tesla after my Y test drive. No core charge! Rear window view worse on Y, seat height better, accelerating at 60 seems a bit quicker. I'll wait for the 4860 battery which will be a game changer.
 

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