2003 express 3500 the abs and park brake lights are on

I'd start at the Positive batter terminal. These things can get corroded while you weren't looking and cause connections to go brown. Disassemble all connections to the positive take a brass brush and a little spray cleaner and re-assemble...don't forget to clean the negative ground lug..both ends.

My Mechanic worked on it for 7 hours and found a section of the wiring harness that was inside the inner fender, was resting on a sharp piece of metal, and over the years the rubbing caused it to cut into 5 wires and short.!! money well spent, I would of gone nuts trying to fix that one.