Just got in from a few hours of wheelin' on local trails. We got pretty wet/muddy, and also went to the carwash afterward. On the way home, I noticed that pressing the brake pedal was causing the interior lighting (IE. instrument cluster, radio, etc..) to change to the brightness of when headlamps are turned on (letting off the brake pedal results in the brightness reverting back to normal). I checked all of the running/brake lights, and all are operational, as I thought this may be some type of warning that a bulb was out, etc... I'm assuming it's probably just some electrical weirdness from the all the water, but was wondering if anyone else had run into this issue? I tried searching the forum and RAVE, w/out success.

cheers,
rich

 

Every GM car I have ever owned did this from brand new, the fault was to small of a battery from the factory and the alt being to small and it could not keep up with the added amp draw.
When the OEM battery went bad I always installed the biggest (amp) battery I could and the problem always went away.

So...have your battery and alt tested if it continues after everything is dry.

 

Thanks Spike, appreciate the reply.

 

you can also try an alternator test with a midtronics tester or equal, It's possible their is a shorted diode in it to.