I'm the new owner of a 2006 Mini Cooper S. I practically got it for free because it has major electrical issues. Almost all the interior electronics are dead. Gauge cluster does not work whatsoever. The navigation screen turns on, but displays only solid white. Climate control panel does not work. The radio works, and the power window and lock switches work, but that's about it. I can turn the headlights on and off, but the parking lights stay on after the car is off and key is removed, until the battery is discharged. This problem used to be intermittent, but is now constant. The car starts, runs, and drives perfectly fine despite this.

The car had a water leak, which I observed dripping from the headliner, onto the rear view mirror, and down onto the dash/navigation screen. You can see a little water behind the nav screen, but it still works. There was also water running down the A pillar and under the driver side carpet.

I connected my diagnostic tool to the car and there were no codes in any modules stored, however it could not detect or communicate with the PCM. I suspected that the CANBUS has crashed, and that either the nav or something else in the dash had water intrusion and was shorting it to ground. I unplugged the nav, radio, climate control, and switch panel one by one, disconnecting and reconnecting the battery between to see if this fixed the problem, but no improvement.

After reading other threads with similar, but not as severe situations, I checked the BCM for water damage and it was perfectly fine. Passenger side appeared dry. I checked the connectors around and under the fuse box on the driver side for corrosion and they were also fine.

Is it possible the BCM could still be the culprit, despite not being directly exposed to water? From what I've read here, they seem pretty fragile. Is there anywhere/anything else I should check?

 

This video is of a slightly older base model ('02 Cooper) but the same info applies to your model.


Good luck