Troubleshooting Dim Trailer Tail and Brake Lights when Connected to a 1993 Jeep Grand Cherokee

Question:

here is the deal my trailer lights r dim brakes and tail but hooked my trailer up to buddies truck and bright as day i had my plug installed at trailer hitch place and they used those things that u crimp on wires so what do i do to fix this it has to b in my jeep 1993 jeep grand cherokee

asked by: eddie

Expert Reply:

This sounds like a weak ground connection on the vehicle side trailer connector. Make sure that the ground is attached to a clean and corrosion free bare metal surface. There should be no paint or corrosion where it is grounded. If it is attached to a common ground then you might have better luck moving it to a ground by itself. Also make sure that the trailer connector is clean and free of corrosion inside and out.

If you feel that the wiring connectors installed on your vehicle are inferior causing the dim lights, I would recommend taking off the crimp on connectors one at a time and soldering the connections with solder, # FL0803484, and a soldering iron.

If soldering the connections does not solve the issue, a powered converter that requires a direct connection to the vehicle battery to power the lights on the trailer would be recommended. This way, the power needed by passes your vehicle wiring, while the trailer lights still receive a signal from the vehicle. They are just getting their power directly from the vehicle battery. This should solve the problem you are having with dim lights, as long as your trailer does not have too many lights on it.

If your trailer has extra lights on it then you may need to upgrade to the Tekonsha Circuit Protected ZCI Wiring Harness, # 119250KIT. This kit will handle more lights on the trailer and protect your vehicle wiring from short circuit situations.

expert reply by: Michael H