'91 Q45: Pressing brake turns off dash lights?

[ti286]

I've seen this problem here before, but can't find the post or the solution.

Symptoms:

1. When headlights are on, pressing down the brake turns off the lights that illuminate the instrument cluster.2. When the headlights are off, braking causes the radio/heater control displays to dim to night-time settings; letting go of brake returns lighting to full daylight settings.3. Computer displays "Taillamp inoperative."4. With headlights on, rear taillamps are out.

Attempted fix:1. Checked fuses. "ILL" 10 amp fuse is blown. Replaced fuse. Fuse blows soon thereafter.

[ti286]

Okay, I found the problem. A rear brake light had melted at its base, causing a short in the system. For some reason the short was activating the parking lights, which were dimming the interior lights.

Off to the junkyard to find a new taillight housing...

[DAEDALUS]

Check them both for signs of melting/burning. The spring-loaded bases begin to melt first often, and then the terminals "sink" into the base, which increases resistance even more, until everything goes. Sitting at long lights gets those bulbs pretty darn hot. Glad you were able to figure out the cause; hopefully new sockets will cure the symptoms.

Oh, if you want brand new parts I recall them being around $15-20 each from Joe. Might be worth it to have new stuff and save a trip to the yard.