Troubleshooting Trailer Wiring Install on 2012 Jeep Grand Cherokee
Question:
The trailer lights do not work after we installed an after market plugs had a factory pig tail
asked by: Paul
Expert Reply:
We first want to determine if the problem is the new trailer wiring harness you installed or if it's possibly a problem on the trailer wiring/connectors.
First thing you should do at this point is test the 4-way of the wiring harness with a circuit tester like # PTW2993 for voltage on all of the right pins when the taillight signals are being applied. Just like in the video I attached.
If the voltage checks out there but the trailer lights still don't function right then the problem is on the trailer wiring. That would mean that problem is either due to a ground issue or a short issue.
Make sure that the trailer side connector are clean and free of corrosion inside and out. The main connector grounds should be attached to clean and corrosion free bare metal surfaces. The light grounds should also 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.
If the problem is on the vehicle side then I would first recommend you double check how the harness is installed on your vehicle, make sure all of the connections are good and tight. You should check all towing related fuses and relays as well.
Products Referenced in This Question
Product Page this Question was Asked From
Tekonsha Plug-In Wiring Adapter for Electric Brake Controllers
- Accessories and Parts
- Trailer Brake Controller
- Wiring Adapter
- Plugs into Brake Controller
- Tekonsha
more information >
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