Troubleshooting Dim Turn Signal and No Turn Signal with Running Lights On Trailer

Question:

with left turn signal on flashing right side real dim flashing when you turn lights on left side stops flashing.

asked by: Tom

Expert Reply:

What you are describing sounds like you have a bad or weak ground on the trailer. Any time you see dim lights or certain functions not working when others are turned on (like with your left turn signal when the running lights are on) this usually means a weak ground connection isn't allowing for enough power to travel back to the assemblies.

I first recommend checking the trailer's main harness ground to make sure it is securely attached to a clean bare metal surface that's free of any debris or corrosion. You will then want to do the same thing with the light assemblies themselves, whether they ground through a dedicated wire or through their mounting hardware. It might be worth it to remove all the grounds, sand down the frame surace where they're mounted, and then reattach them just to be sure they are secure.

If you still have the same issue please let me know and we can continue to troubleshoot. I have also attached a troubleshooting article that you might find helpful.

expert reply by: Chris R