12 V battery

12 V battery

3 week old Model X has message that says: Replace 12 volt battery.

Called SC and was told it could be a sensor, but a ranger will come out to me and replace.

Any ideas why it would be needed to replace so soon. Driven about 750 miles. Did not discharge less than 50 miles.

ir | 15 April 2017

12V battery has nothing to do with the big 400V traction battery. Mileage and how much you discharge the main battery is irrelevant.

The 12V battery powers the computers which tend to be running all the time, even when parked. There used to be problems with the particular 12V not liking that discharge pattern.

Solarman004 | 16 April 2017

Others with this problem have found it to be a faulty DC-DC contactor that keeps the 12V battery charged from the traction battery.

Fast Girl | 16 April 2017

Hmmmm, sounds like a another "general" message from an engineer, I guess it could have been worse. It could have read "Error code X10486622_3827664hk784444" Contact service" :-)

joe_jet | 22 April 2017

Kind of strange to have a heavy old technology spillable lead acid battery in such a high tech vehicle. I plan to replace mine with a LiFePO when it goes | 22 April 2017

@joe - Not a spillable lead acid battery. Tesla uses a deep discharge sealed absorbed glass mat battery.

Should you go with a LiFePO battery, you may be replacing it every 6 months. The 12v battery gets charged/discharged a number of times each day from the main pack battery. A lithium battery is actually a poor choice for a replacement in the Tesla although it might be a good replacement in an ICE car.