Only Trailer Side Marker Lights Work After Installing Hopkins Harness on a 2005 Chevy Equinox

Question:

I just bought a 4flat taillight converter from you #41235. When the car lights are on the only lights that will work are the side marker lights. What is the solution?

asked by: Laura M

Expert Reply:

The problem you are having sounds like it could be an overload or a ground problem. The first thing to do is test the vehicle side 4-Way without the trailer connected by using a circuit tester such as # PTW2993.

First make sure that the wires going into the converter box on harness # 31235 (41235) have power when they are supposed to. If they do not, then that indicates a problem on the vehicle side that will need to be tracked down. If the wires do have power when they should on the input side move over to the output side (4-Way). If the wires do not have power when they are supposed to on the output side, then that indicates a problem with the converter and the harness will need to be replaced.

For the possible ground issue make sure that the trailer side connector is clean and free of corrosion. The main trailer connector ground and the grounds for all of the lights should be attached to clean and corrosion free bare metal surfaces. If there is anything between a light ground and the metal trailer frame or if the trailer has an aluminum frame, tilt bed, or folding tongue, any of these things can interrupt the ground. Running jumper wires from the light grounds to the main trailer connector ground can help.

To check for an overload condition, you can disconnect some of the lights. Then if all the other lights start working then it was likely an overload; the lights draw more power than the harness can handle. The solution to this is to switch the trailer to LED lights that draw a fraction of the power.

expert reply by: Michael H