So I have replaced the break light switch, relay, multi switch, and the fuse. Even with the switch unplugged the lights stay on. The only way for the break lights to go off is to in plug the fuse under the hood.

 

All the time? Even when ignition is off?

 

Yes sadly I think the harness has burnt up and melted something.

 

Time to start tracing wires.......

Is it the brake lights, or the running lights that are staying on? Headlight switches were notorious for melting down on these trucks.

 

It’s the brake lights.The running lights come on when the brake lamp fuse is pulled. I can try replacing the headlight switch. I also disabled the trailer lights completely. So unless I see something burnt in the headlight switch I believe the whole harness is fried.

 

Commente to be notify
.

 

Check the brake switch then. Just unplug it, and see if the lights go out.

 

? Wrong thread?

 

No idea......

 

It happens