12v Battery life

[islandbayy]

I'm sure it was the Tesla Mobile technician who said something like 'if the plates inside the battery touch, the warning will always show even if the battery is charged back up again, there's no way to reset it other than replace the battery'.

I could be wrong, all I know is that the warning will never go away fully, despite me knowing 100% that the battery is perfectly ok

Pull the first responder loop, disconnect the negative terminal on the battery, wait 10 minutes, reconnect, and error will be gone.
Although, this is a good way to stop getting updates if you don't want them, since they won't install with the 12v warning.

 

[brkaus]

BTW, to the best of my knowledge, plates inside the battery don't just touch and untouch. They can grow a short, but nothing to do with a low battery and it doesn't cure.

 

[Tevvy]

Pull the first responder loop, disconnect the negative terminal on the battery, wait 10 minutes, reconnect, and error will be gone.
Although, this is a good way to stop getting updates if you don't want them, since they won't install with the 12v warning.

Thats the same as toggling the wheel options and it does go away (for a while) but sure as eggs are eggs it’s back again shortly afterwards.

 

[Tevvy]

Does your car sleep? Low phantom drain?

I’ve nothing to compare it to but I’d say I have high phantom drain (7 miles a day) if I leave it at the airport.

 

[brkaus]

I’ve nothing to compare it to but I’d say I have high phantom drain (7 miles a day) if I leave it at the airport.

Yea. Drain is so variable it’s hard to say. That does sound high fir long term parking.

One clue can be how long it takes the app to respond after sitting overnight.

What year/type of Tesla?

 

[cmaster]

I’ve had the ‘replace 12v battery’ warning on for 3 years and 50k miles and have just ignored it. I have a battery monitor attached and it never dips below 12v. Theres clearly nothing wrong with it. It started when I drained it inadvertently whilst being in the car stationary for a long period of time. I just charged it back up and all was good. But the warning continues to show. I have to reset it by doing the ‘wheel configuration’ change to get it to install a software update but it always comes back on after a few miles of driving.

I heard once that it triggers something in the battery once it goes flat the first time, and following that it will always show the warning even though there’s clearly nothing wrong with it.

A worn 12 volt battery put more work onto the DC-DC converter that also powers the PTC Heater core. So, overtime, it will definitely blow the fuse in the DC/DC converter box. Something to keep in mind. Relatively expensive repair.