Has Tesla done anything to correct the problem owners have had with charging their 12 volt batteries? I have had to replace 3 12 volt batteries due to the fact they were not getting charged.
What's the time frame of your 12 volt battery problem? Did this occur under warranty?
I ask because I just had my 12 volt battery replaced under warranty. There was no underlying problem identified and when I asked the Service Center employee about it she said this happens regularly. I asked how often and she said every 1 to 2 years. I left the service center with the intention of upping my Tesla repair credit union sub account cash transfer by $25/month.
Mar '14 delivery, 56,000 miles, still have original 12v battery.
Mar '15 delivery, 20,000 miles, working on my first replacement 12v battery.
Seems to have been solved. Don't hear much about this issue anymore. It's unclear if you've had a battery problem or a charging problem (quite different). If the 12v charger fails, then the 12v battery will not be charged and will be drained and will need replacement when the charger is replaced. So the battery is not really at fault in this case even though it will need replacement.
Note that all new cars have a better 12v battery location, making battery replacement easy.
So what is the warranty period for the onboard 12v charger? If it fails under warranty I would assume they also replace the 12v battery at the same time....is this the case?