Troubleshooting Lighting Function On Trailer Wiring Harnes

A trailer wiring system is grounded to the frame near the coupler and each light also needs to be grounded.

Troubleshooting lighting function on trailer wiring harnes. Most likely the ground wire on the trailer is not secured properly. If your vehicle is not equipped with a working trailer wiring harness there are a number of different solutions to provide the perfect fit for your specific vehicle. Hard wire only vehicle has combined brake and turn signals brake light wire on harness is not grounded. Complete with a color coded trailer wiring diagram for each plug type this guide walks through various trailer wiring installation solution including custom wiring splice in wiring and replacement wiring.

Pay particular attention to all ground connections on both the vehicle and trailer side. An extra pin allows using another extra function. Using one turn signal engages the turn signals on both sides of the trailer. Each component should have its own ground to the frame of the trailer.

If the lights on the tester function properly the problem is the trailer lights or harness and you need to some trailer lights troubleshooting. If there is not a white ground wire coming out of a trailer light then the light is grounded through its mounting studs. Troubleshooting installing new 7 way and connector does not work. Begin by cleaning the ground connections.

Does 12 volt wire on trailer side 7 way have to be connected if trailer does not need 12 volt power. Check for broken wires near the connector. If the white ground wires are not firmly attached to a clean rust and paint free surface there may be an inadequate ground that will not pass enough current for all light functions. For the most part the wiring harness that operates your trailer lights is a closed system.

If the trailer light functions operate as they should then the issue is probably on the vehicle side. Recommended wiring harness for rewiring a 26 foot gooseneck stock trailer. Troubleshooting trailer lights not functioning when headlights are on. Clean the connector photo step 2 below and check again.

Ground problems are the top cause of issues with trailer wiring. If you still have problems make an appointment to have the wiring checked. Harness has been overloaded due to excessive draw from lights or a short in the trailer wiring. 5 wire trailer wiring diagram.

Then one circuit at a time apply the battery positive wire to the contacts on the trailer connector. If the trailer lights flicker on and off there is a good chance the trailer is grounding by way of the hitch instead of through the trailer s wiring connector.