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12V battery disconnected. Vehicle may shut down unexpectedly

12V battery disconnected. Vehicle may shut down unexpectedly

Driving to meet up with a friend and get the "12V battery disconnected. Vehicle may shut down unexpectedly" message. I'm equal distance from the destination and a Tesla Service Center, but it was early on a Saturday. So I went to the meet up and scheduled a mobile service to my home with the app, it made it for 4 days hence. Left the meeting and no more alert message. Stopped by the service center and find the sales office is open, but service is closed. Finished my other two stops with no more warnings. At home, I popped the frunk and the battery cover. Behold! The ground terminal was in fact loose. Fixed that. Model 3 was purchased 9 months ago and was in the service center for a week waiting on parts when the drive unit failed hard after two weeks. Might they have disconnected the 12V battery at that time? These are the facts. Here is the question.

Should I cancel the mobile service visit or keep it? I did not pop off the plastic part that covers the positive battery terminal, so it might also be loose. Should I pop that off and check the positive terminal? Are there any tricks to getting it off and then back on? That part is also for the ventilation.

I kind of found this amusing. Scary for the first 5 minutes.

TeslaTap.com | 23 novembre 2019

I suspect the ground lug was removed for the DU service and they put it back on but forgot to tighten the terminal. By disconnecting the 12v, you are assured the HV pack is disconnected (it requires 12v to close the contactors to provide HV). If you tightened it, and it's all working, I'd cancel the appointment, as it's not worth the time/effort. If you're still concerned, there is no harm to keeping the appointment.

AstroSteve | 23 novembre 2019

Thanks. I'm leaning towards the cancel option after more driving.