No interior lights...need ideas

[sferrv6]

Hi guys, hope you can help...have 87 GN and every time I turn on the headlamps I lose the interior lights... the dash (radio, tach, everything), console shifter, dome light...none of these work. The 5 amp fuse blows everytime. I cleaned the ground wire and checked the head lamp and interior dimmer switch.

Any other things I can look for?

 

[FastRegalWE2]

something is shorting, may be just the headlight switch. You need to get a wiring diagram and start tracing the system.

 

[John Larkin]

One thing you can do that I was taught: Way up under the dash, there is a white plastic cage with several orange wires plugged into it. I think it's a distribution block for interior lights. If you lay on your back under the dash and look straight up you'll see it. Unplug everything that goes to it, turn on car, and start plugging back in one at a time. When you here the fuse pop, you've found the circuit. Mine turned out to be the dome light which had a hot wire grounding out.

 

[dmk2]

Have you messed with the radio lately?

I had the same thing happen to me once. It turned out to be the hot wire on the radio, I think the one that goes to the antenna.