Lost running lights

[Diggler]

I've got a 96 k1500 Silverado. Was on my way to work in the morning and lost running lights (amber ones on the front, and taillights) all of a sudden. When I looked into it, the fuse was blown. It's a 20A fuse. I put another 20A in, the second I hit the switch for parking lights, it blows. If I put a 25A or 30A, it gets screaming hot. I've obviously got a short somewhere, but where do I start?

[2COR517]

The most common area for problems is the taillights. Especially if a trailer hookup has been installed. I would start here. There is a plug "Behind" the rear bumper. You can disconnect all the rear lights here. Put in a new fuse and try it. If it is OK, you have narrowed down the problem. I would pull the taillights and disconnect each light and keep trying till you find the problem.

[Diggler]

Update...I have a circuit breaker (signal relay) with wires I rigged up to plug into both prongs of the fuse location. I put that in and walked around the truck with all lights flashing on and off. I disconnected the taillights at the harness by the rear bumper and it didn't solve the problem. I had all the front lights hanging out and checked all the pigtails, they were fine. I checked the bulbs, they were good except one of them was slightly rotating in the cup. I replaced it, put a fuse back in, and the lights work just fine now. I'm not convinced it's a final fix, but I'll have to keep an eye on it in the meantime.

[2COR517]

Great troubleshooting! I like the signal flasher idea. That's excellent. The mis-installed bulb could cause the short, but like you, i would be on the lookout. You can separate the front and rear harnesses at the firewall. Just pull that one bolt, and it will all come undone. Might be wise to look around for a crushed or abraded harness.