My car decided to die some time between yesterday afternoon and this morning. Went out this morning and the 12V battery was utterly and completely dead - I had to unlock it manually using the metal key. Getting in the car - 0 response on any screen, no lights, nothing.
I had gone to the store yesterday for a quick run to get something to eat, maybe 5 miles round trip and when I parked the car had approximately 45% charge remaining. There is no way the doors were open or any type of accessory was left on that could have drained it. I took a look at my driveway camera and it was not accidentally hitting the hazard lights, either. No idea what caused it.
Called AAA for a jump today and drove the car around for a while. Still turned on okay when I checked on it again later this afternoon. Internet/LTE seems to be functioning normally. Car status shows nothing.
Only thing to report is that:
SOS on red. Ecall service required (on screen)
I plan on running it below 20% then charging to 90% as mentioned earlier, followed by a TCAM reset if that does not remedy the issue.