Trailer Lights Go Dim When Multiple Light Functions are Used at the Same Time

Question:

The running lights and brake lights work when they are by themselves, but when I have the running lights on and I hit the brakes, it all goes dim. as well as when i turn on a blinker the other side goes dim when the blinker comes on and then gets bright when it is off. The trailer was not grounded so i used a grinder and ground down a piece of the frame to bare metal, and placed a tec screw to hold the ground to the frame and it is still happening.

asked by: Cole S

Expert Reply:

You are definitely on the right track for troubleshooting your trailer lights going dim. The first thing that we recommend doing is checking all of the grounds on your trailer making sure that they are secure and connected to a clean, bare metal surface. You will also want to check your vehicle and trailer connector to make sure that they are free of any debris or corrosion.

The next thing to look at is to see if you have too many lights on your trailer. You can test this by disconnecting a light at a time to see if that fixes the problem. Too many trailer lights can overload the harness. This could be why your lights are going dim.

If this doesn't fix your problem let me know and I can help you troubleshoot further.

expert reply by: Jon G