Join Date: Jan 2004
Location: Pasadena, Texas
According the the electrical schematic for my 86, fuse 10 supplies power to the Left Front/Right Rear parking and side marker lights, the trunk light, and the Light Dimmer. When fuse 10 blows you should lose the previously mentioned parking and side marker lights, the trunk light, and everything under rheostat control.
Logically it should be a problem in one of those circuits or that portion of the switch but I don't think it would be the switch as there is no ground connection in there.
Try turning on just the parking lights, does the fuse blow?
unplug/disconnect the LF/RR & trunk lights, replace the fuse and try again. If you have a 12v test light that you can connect in place of the fuse it will save a few fuses. The light will illuminate when a circuit is complete and go out when the circuit is open. This will require getting to the rear of the dimmer and unplugging it to eliminate everything under rheostat control.
with everything disconnected if the test lamp is illuminated then there is a wiring problem or something on that circuit is still connected. If the lamp is out plug things in one by one. A short will make the test lamp brightest otherwise it is in series with the other lamp(s) and should be dimmer than normal.