Trailer Running Lights Blow a Fuse on a 2005 Chevy Silverado when Towing Different Trailers

Expert Reply:

There is either too much power draw from the trailer lights when the running lights are on (if the trailers have a lot of running lights, this is possible) or there is a short in the trailer connector, vehicle side or wiring somewhere.

You can check the amperage draw of the lights by looking at the light housing where the wires attach. There may be information on how much power draw the lights require. Otherwise, you would need to use a multi-meter like # BTMT15 if needed to test the power draw before the fuse blows again. To prevent the fuse from blowing when testing the amperage draw of the lights, it would be best to disconnect all the lights and test one at a time.

Check the vehicle side connector for dirt and corrosion inside the plug and at the back where the wires attach. Clean out any corrosion you find. Next you can try to check the wiring leading to the front of the vehicle for breaks in the wires that might be touching bare metal causing a short or overload situation.

If could also be a short in the power distribution box under the hood. You would need a qualified mechanic to check it to see if that is the problem.

expert reply by: Michael H