I looked through the threads but didn't see anything, so I'll ask the question. Just recently the auxiliary stop light in my 88 328 GTS went out. Tried replacing the bulbs but that didn't help. Checked the fuses and they are OK. What am I missing here? All of my other rear brake lights work exept the auxiliary light about the rear window. Any suggestions?
Check for voltage at the lamp, check the grounds, then trace the wiring and check for loose (or burned) connectors.
I checked the voltage at the lamp last night and it was about .3 volts when the brake was depressed (seems low). When the brake wasn't depressed it didn't read any voltage. So that tells me the lamp is getting a signal, just a small one. Also, when I took one of the bulbs out and then press the brake pedal, the one remaining bulb slowly lit (took a couple of seconds) to a small glow. When I put the second bulb back in the series, no glow from either bulb. I checked the connector betweent the light harness and the main harness and that seemed OK. So knowing that the lamp is getting a signal, albeit a small one, there is probably a ground problem. I just don't know if it's a lack of ground or a short. Further comments to this problem would be appreciated.
