Troubleshooting 1990 GMC 1500 that Blows Fuses w Trailer when Running Lights/Brake Lights Applied

Question:

1990 GMC 1500k truck. When the running lights are on and then the brakes apply will blow a 15 amp fuse in the truck.

asked by: Bill

Expert Reply:

Sounds like your trailer lights are drawing too much amperage for your vehicle wiring and that is why the fuse is blowing. When your running lights and brake lights are applied the wiring of your trailer is drawing the most it will draw.

The easiest way to fix this problem is to replace the incandescent trailer lights on your trailer with LEDs. LEDs draw considerably less than incandescent bulbs so the fuse should stop blowing. I attached a page that has all of our LED trailer lights for you to check out.

I attached an FAQ on trailer wiring for you to check out also.

expert reply by: Jameson C