12V Battery shortage??

[fsch]

Sorry if this is a bit OT, but why do we even need 12V batteries in a Tesla?

Couldn't they just tap into a portion of the main battery bank?

Actually, from what I read here and elsewhere, the 12V battery is indeed needed at least to activate the main relay of the large battery, but in addition, when the main relay is activated, the high-power circuit it is connected to is also activated and consumes non-negligible amounts of energy, even if it's doing nothing. So the strategy here is to maintain the 12V activities of the car (network, key detection, what else) with the 12V battery, and when it starts to be depleted, engage the large battery for a relatively short period of time to recharge the 12V battery, and go back to sleep. However, the battery is small compared to the one in ICE cars, so these "12V activities" take only ~3h to deplete the 12V battery. As a result, it is cycled several times a day, which may explain its small durability. Although this replacement occurs after 5 years of the car life, and I did have to change the battery after 6-7 years on my last ICE car.

 

[iKhalid]

Ummm... Mine is in its 4th year (just hit 100k km) with the original 12v battery.

Apparently I jinxed my car. I just got the 12v battery warning ⚠ .

 

[cwave1]

My first Model S had the 12V warning come on on the way to trade it in for my current Model S at Lawrence.

Maybe she was trying to tell me something?

 

[Evoforce]

I have one to sell. PM for details.

 

[bodhigirl1964]

I got this warning last Friday. Getting in touch with Los Angeles service: impossible. Phone message system is full and has been for five days. I drove there to get a battery. They told me mobile service would contact me. No one contacted me.
I called another local service center and was told 12v batteries are backordered.
This is not acceptable.
I love my Tesla and their service is sub par.