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One month old P85 with 12V battery issue

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According to the Bellevue SC they looked at the logs and traced this to a known issue with 5.8. They said the issue is that with shore-power battery pack warming (a new feature?) at times the contacts remain open and can drain the 12V battery. A fix is supposedly going to be pushed soon.

Additional Details

  • They asked me to see if the car would go into drive.
  • When I hit the brake pedal both consoles re-booted and then charging started. Not certain whether the re-boot was them or me.
  • After charging completed the 12V alert went away.
  • They told me that with the cold weather I should disable scheduled charging until the fix comes out. They told me the fix might be “silent” and not result in an alarm clock update notice.
  • Plug in every day when I get home but use scheduled charging at 3am.
  • I am currently on the 1.49.24 release.
  • Drive 30 - 60 miles/day. Total miles ~1300.
  • They told me the 12V didn't fully discharge and so is still healthy.

They told me the car was fine to drive. No issues on the commute.
 
I had a similar issue today. I was getting two error messages. It was around 10 F in Chicago today. I have not had any problems in the past. After talking to the SC, they want to take a look.
IMG_20131209_222134_608 (2).jpg
 
According to the Bellevue SC they looked at the logs and traced this to a known issue with 5.8. They said the issue is that with shore-power battery pack warming (a new feature?) at times the contacts remain open and can drain the 12V battery. A fix is supposedly going to be pushed soon.

Additional Details

  • They asked me to see if the car would go into drive.
  • When I hit the brake pedal both consoles re-booted and then charging started. Not certain whether the re-boot was them or me.
  • After charging completed the 12V alert went away.
  • They told me that with the cold weather I should disable scheduled charging until the fix comes out. They told me the fix might be “silent” and not result in an alarm clock update notice.
  • Plug in every day when I get home but use scheduled charging at 3am.
  • I am currently on the 1.49.24 release.
  • Drive 30 - 60 miles/day. Total miles ~1300.
  • They told me the 12V didn't fully discharge and so is still healthy.

They told me the car was fine to drive. No issues on the commute.

Great information, thanks!
 
I also had a problem with a scheduled charge during cold weather.

At the time my car was running 1.49.24. It was the first time I tried a scheduled charge at 5am rather than 9pm or 11pm at night. Temps were just under 32F.

My car woke up at 5am and tried to start charging but failed. I woke to an uncharged car, a near dead 12V battery, and an odd clicking noise repeating over and over (likely the reason for the drained 12V).

I took the following video of the clicking sound for diagnostic purposes.


I was plugged into a 110-120V outlet via an extension cord. However, I have used this cord and outlet many times with no problem.
Tech on the phone confirmed the 12V was low. Once I started the car and then plugged it into my 240V outlet it recharged the 12V and cleared the fault. Tesla pulled the logs and could see the problem as well as they said the 12V was showing as good and that I should be fine to drive the car.
 
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Yup. That was my experience. Since .30 I've started using scheduled charge again (3am) - but my garage temps are now consistently above 41F. So I can't tell if .30 fixed or whether the temperature is the fix. I was supposed to get a call back from the SC letting me know when the fix was pushed - nada.
 
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It appears my car had the issue, but I'm told the update fixed it. Ironically I got the warning message and the update the same evening.

Edit: I'm told there is still a firmware update in the works, and to discontinue timed charging if the problem recurs.
 
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I also had a problem with a scheduled charge during cold weather.

At the time my car was running 1.49.24. It was the first time I tried a scheduled charge at 5am rather than 9pm or 11pm at night. Temps were just under 32F.

My car woke up at 5am and tried to start charging but failed. I woke to an uncharged car, a near dead 12V battery, and an odd clicking noise repeating over and over (likely the reason for the drained 12V).

I had very similar symptoms on Dec 1st, 2013 with my EU Model S 60kWh. Firmware 1.49.24. Plugged into 13A 230V single phase outlet, charging set to start early in the morning. Night was chilly around 0°C. Found the car not fully charged, low 12V battery warning, clicking noises.