Just purchased 1993 K2500, all engine lights work, head interior and tail all OK, radio lamps on until you turn on head lights then they go out, dash lamps will never work, replaced head lamp switch and seperate dimmer switch, still no difference, fuse OK not burned out?? What could I be missing. Thanks for any help

 

got something grounding out. Trace the wires and put a test light on them. Try replacing bulbs in the instrument cluster for the dash lights not working.

 

id say ground problem somewhere.

 

Thank you I will try and locate a wiring guide to find ground wire will look and let you know.

 

Heres your wiring schematic your looking for.

 

Thank you MUCH for the Diagram..will be looking today.