Service Required after 12v battery replacement

[Jlahrens30]

it sure seems like there are alot of these 12v related issues floating around these days. I had the dreaded car might not restart a few weeks ago. SC replaced the rear drive unit. 3 days later i get it again. This time i pay to for diag...replace the battery heater...same error codes and still truing to find the gremlin

 

[Crutonius]

A couple things come to mind. May or may not help.

1. If possible try a different service center. The results you're getting from this one seem... odd.

2. Try a regular 12v car battery using a jumper cable. Maybe the battery you've got isn't be detected for whatever reason and the dc to dc converted doesn't turn on.

3. Here's a video detailing how to test the dc to dc converter.

. Doesn't seem too difficult to check.

 

[Gumball]

To me, this sounds like bad contactors. Had the same on a 2013 car, and with (if i remember correct) the same alerts on the screen.

 

[LaurS]

While replacing the cabin air filter I decided to look at the battery. The 12V battery sensor seemed to have some oxide built on the jumper. I removed it and clean it. Of course I forgot to plug the 12V connector back in, and I got that schedule service warning. It cleared after I put the connector back.

I noticed that the 12V battery seems to be bulging on the side. Basically the red cover is flat, but the red is rounded a bit. It seems quite evenly all the way down. I might be how the battery is built. The positive side is not easy to see or feel. Does anybody know if that is how the new batteries are? Do I need to prepare for a 12V battery change? Below is a picture from the internet for the type of battery that I have.

 

[wycolo]

Finally found these data from some time ago. Alleges but with graphs & voltages to prove the thesis that over-voltage spikes did/do exist in TM managing their 12 volt realm in the ModelS. These spikes will likely destroy any lithium ion 12v battery over time. So to be safe I replaced my dead stock 12v batt with another lead acid but a bit bigger. However I finally fulfilled a long held dream of relocating the batt forward into the frunk for easy access, like the newer MS's enjoy.

I have not checked with the blogspot poster, all rights belong to him.
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