Just had my first customer support call into Tesla.
A red warning indicator on the Center Console told me to call Tesla Service.
I call the support center and after being routed several times had to leave a voicemail. I got a call back 10 minutes later. I gave the service rep my VIN so they could check on the vehicle remotely. The service rep told me the issue was that the 12V battery had run low. The car should have autonomic systems that detect and address the low charge, but for now, the remedy was to manually initiate a charge cycle, even though I was at 90% of my standard charge.
Interestingly, the service rep also had me lower the 40amp max amp setting to 12amps so the charge cycle could get drawn out more. I asked how this helped the 12V battery and the service rep said that longer charge cycles are better for both the 12V battery and the main battery. In general, he recommended that I reduce the 40amp max setting for my 14-50 outlet charger to 25 or 30 amps so that I can draw out the charging when I charge overnight. Then he said that the fast charging at superchargers was detrimental to the battery.
I don't see how the slower charge cycle hurts me as I have plenty of time to get to standard range overnight. However, I'd like to know if any other owners have been given this same advice and can help me understand if slower/faster charging affects battery health. Also, has anyone else had issues with a low 12V battery? any idea what conditions cause the 12V battery to go too low and why the car sometimes may not be able to address this on its own?