Trailer Lights Stopped Working when Connected to a 2010 Ford Escape

Published 08/07/2015

Products Featured in This Question

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(180)

$72.73

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(605)

$71.90

Hook Probe Circuit Tester

(60)

$12.41

Question:

I installed this on my 2010 ford escape. I installed brand new lights and wiring harness on my trailer. Everything worked when I tested it. A few days later I went to use my trailer and no lights work. I checked the fuse on the harness and it wasnt blown. I checked all connections including grounds and they were all good. What else can I do to make my lights work again?

asked by: Matt

Expert Reply:

We will need to determine where the problem is. To do this you will need a circuit tester such as # PTW2993. Test the vehicle side connector with the circuit tester while someone sits in the 2010 Ford Escape and activates the lighting functions (turn signals, brake lights, and running lights) while you test the connector.

If there is no power on the 4-Way when performing the test, then perform the same test only this time test the wires going into the converter from the Escape (instead of the output wires to the 4-Way). If there is power going into the converter but not coming out, make sure that the single white ground wire is attached to a clean bare metal surface (no paint or coating). And make sure the power wire attached to the battery has power. Fix as needed.

If there is still no power then that indicates a problem inside the converter and it will need to be replaced.

If everything does work on the vehicle side then the issue is on the trailer and is likely a bad ground. Make sure that the vehicle side and trailer side connectors 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 trailer wiring harness does need to be replaced then I recommend Tow Ready harness # 118551.