Trailer Lights on Passenger Side of Trailer Are Dim and Sometimes Go Out

Updated 08/25/2010 | Published 08/24/2010

Question:

Driver side of trailer is ok, But passager, side amber light does not work and turn signal and running light on back dim, also when I hit the brakes, the left side brake light goes out and the right side is ok..

asked by: Bill S

Expert Reply:

It sounds like you may have a loose or bad connection somewhere in the trailer wiring. I would start by checking the ground wires and make sure they have a good contact to metal and are tight and look over the wires to make sure they are in good shape and not damaged.

Another ground point you may want to check is where the light brackets connect to the frame of the trailer, sometimes the connection can corrode or rust where the lights bolt to the frame and will cause a bad ground.

Next, I would check the wiring on the driver side of the trailer since it is functioning properly. I would make sure the passenger wires are ran like the driver side and check the connection points and make sure there are no cut or frayed wires.

Another thing you may want to check is the bulbs, to make sure that they are connected in the light sockets or not burned out.

Also, you could check the wring connection from the trailer to your vehicle to make sure there is no corrosion in the connector.

I have linked an FAQ on Trailer Wiring below that may also be helpful.

expert reply by: Reno H