Two days ago while driving my 2001 Trooper, my instrument lights and running (parking) lights all went out. Headlights work fine, as does emergency flashers, turn signals and brake lights. Checked fuse and it was blown. Replace and the fuse blew immediately. If I remember correctly, all the lights went out when I stepped on the brakes while traveling at about 50 MPH. What could have caused the fuse to blow? Seems like a short somewhere? But, there were not previous issues and no work was done on the vehicles electrical system in the past 5 years. Any ideas? Thanks for any information

 

I'd be looking for damaged wiring under the dash. If you stomped the brakes, and they blew, look for wires hanging down under the dash that may have been pinched or tugged on near the brake pedal linkage.
Another possibility would be the harness going forward in the engine bay to the front lights. Missalignment of body panels in a hard braking moment, or a hard pull on the harness could cause a short like this.

Could be a lot of places. If the rig has been off road, and suffered damage, the list gets pretty long.

CJ

 

CJ - thanks for the suggestions. I found the problem to be a shorted out trailer hitch harness. It was rubbing on a frame part!

 

CJ - found the problem to be a shorted out trailer hitch wiring harness. Wires were rubbing on frame.

 

Marvelous!

CJ