Saturntech9, for pre1992 models there are not many system diagrams. You need to check the wiring under engine compartment.
Perform the following test first.
At headlight connector, test the following wires for battery voltage with headlight switch turned on.
Red/Yellow (right side)
Orange (right side)
If you have battery voltage with any lights not working, ground the Pink (right headlight) or Pink/Black (left headlight) and retest. If lights comes on, the light sensor or its wiring is faulty.
If battery voltage is not available under the lighting positions, you have a bad light switch.
Images (click to enlarge)
Saturday, July 28th, 2012 AT 1:39 PM