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What powers Backup power supply (BPS)?


Nov 6, 2011
Trondheim, Norway
When BPS is running, which bricks does it take its power from?

I ask about a Roadster 2.0 that has a 12 volts battery, not a Roadster 1.5.
I have problem with brick #28 never reaching the same voltage as the other bricks when the car is charged, even if the car is plugged in and has been balancing in standard charging mode for two weeks (car has not been driven in this period).
Tesla Service reported that my BPS is active and there is also communication problems with "Battery Monitor Board(BMB)". Both of these are in the main battery. The car never shuts down.
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