When I have my switch in the marker light position, the driver's side marker lights work but the passenger's side doesn't. When I put the switch in the headlight position, all of the marker lights work. I checked the marker light fuses and they are good. When in the marker light position the front passenger bulb shows no voltage, when in the headlight position the bulb shows 12 volts. I checked the pins on the headlight switch without the connector on it and when I am in the marker and headlight positions I have continuity between the power and right and left marker light pins. I checked the voltage at the connector while it was connected to the headlight switch. When it is in the marker and headlight positions it shows 12 volts on both the right and left marker light wires. I can run a jumper from the power wire to the left marker light wire and they light up. When I put the jumper on the right marker light wire I get nothing. It seems like everything is working fine at the switch. I am confused as to how it is the right marker lights have no voltage at the marker light position but have power at the headlight position.

 

It actually could be the contacts inside the switch - did you disassemble and sand/clean the contacts? Might help fix it.

 

Haven't tried that yet. When I bought the car, I found out the headlight switch had stopped working because the plastic holding the contacts inside had melted. So I took it apart and fixed it. Could have something to do with that. Possibly it's not making contact inside at the marker light position but is at the headlight position? I'll have to check that out. I'm going to check and make sure I have continuity between the wire at the switch and at the bulb to see if I have a short or a broken wire. Does anyone know if I'm correct in thinking that the wire goes from the switch straight to the bulb and doesn't have a relay or something it goes through?