i'd agree with a bad ground issue.

Originally Posted by
Javier
power to the circuits should be OK (best way to confirm is to test bulb light contacts, as one of them should have 12V to ground when lights on). Then ground path trough the sun visor switches should be checked. If I recall properly, it is a combination of a contact in the parking socket for the sun visor prong, and a switch in the mirror sliding cover. Check those tricky ground switches as they may be dirty. Hard to reach, I guess, have never tried.
Javier
95 E34 530I V2.37
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