Switch the console switches and see if it works.

Check the voltage at the switch terminals on the passenger side. I think more than one should have 12V. If the console swithes are good it has to be a bad wire (could be on the ground side).

__________________
Charles
1983 300D, bought new, 215k+ miles, donated to Purple Hearts veterans charity but I have parts for sale: http://www.peachparts.com/shopforum/showthread.php?t=296386