the last few days I've noticed the G a little slower to start. This morning it barely started when my wife was going to work, so I offered to take it instead. Leaving work this afternoon it was better, but when I got it home, it wouldn't start after being in the driveway for 10 minutes.
I didn't want to boost off the Tesla, so I plugged it into a charger at 10 amps, waited 5 minutes, then started it. Connecting the multimeter at warm idle showed me 14.5v.
Shutting it off, the battery dropped to 12.4v, then dropped to 11.6v over the next 15 minutes. So I left the test leads on there,went and had dinner,and came back to check one hour later. 12.16v.
Now 4 hours later the meter is showing 12.28v.

What gives? Battery? VCV? BCM? It seems like when it is hot the battery is draining.

B

 

The vent control valve sometimes fails to shut off, draining the battery as you describe.

I had a 2009 and the dealer replaced the valve and the battery under warranty.

There's a TSB: #ITB01-010A

Good luck...