When I bought my '79 240D, the dash lights were not working. It was the common problem with the dimmer in the instrument cluster being broke, and I wired it so the dash lights would be on full brightness. However, I recently realized that there are other interior lights (heater knobs, headlight knob, etc.) that should be coming on. None of these work. Both dome lights do work properly. I can't find any fixes for this (or maybe I'm just not very observant). Any thoughts?