Parking and dash panel lights on ALL the time on 96 GM Astro: No codes

Symptoms:

Parking lights including license plate lights, dome and dash panel lights are on all the time even with the ignition off. There are no codes when scanned but this problem started after a trailer hitch package was installed.

Basic Concept:

After the installation of your trailer hitch package which includes the trailer harness wires, double check to make sure the connection to the terminals are correct. Sometimes, the wiring path is crossed causing a short creating a back feed that continuously supply power to these lights.

Repair Strategies:

Use a wiring diagram to verify the flow of power to the trailer harness. If necessary, unplug the fuses one at a time until the light goes out. the last fuse that was touched is the possible circuit. Also, the dash lights can be tested for power and ground supplies going to the headlight switch after dropping the steering wheel column cover (see picture shown on the left).

Note:

To get the appropiate wiring diagram for the lights, please contact ATS.