Every light on my 1994 Chevrolet Silverado 1500 4x4 works. Except the headlights. All of the bulbs are good, and I've twisted the wires in the harness, and they're good too. There aren't any fuses or relays for the headlights that I know of, so what do I do from here? : X
The only things that would probably be wrong are.
-Headlamp Dimmer Switch
-Headlight Switch assembly
-wiring between the two
The dimmer switch splits the power to the high and low beams, so if both dont work, you have lost power by the time it goes thru the dimmer switch. If you can get to the wiring on the dimmer switch, check for power on Pin D (Yellow wire) with the light switch on. If you have power, then it is probably the dimmer switch gone bad. No power, and it is probably the light switch itself.