Troubleshooting Trailer Wiring When Lights All Go Out When Brakes Are Applied

Question:

My 2008 Ranger has a flat 4 connector that goes to the 7 way trailer connector and all was working properly till I pulled a sharp turn and the wires from the trailer connector came off. I followed the wire connections per the diagram and all lights seem to be working, along with the blinkers but when I hit the brake lights all lights are out. Im perplexed at this point.

asked by: Larry

Expert Reply:

It sounds like the ground wire may be the culprit and causing the issues you are having.

Check the ground wire to make sure it is securely attached to a clean metal surface. Also make sure it did not get pulled out of the trailer connector when you made the sharp turn.

If the ground checks out okay, you may want to use a circuit tester like part # PTW2993 to check out the pins on the vehicle side trailer connector by function. Have someone sit in the cab of the truck and run through the functions while you check the connector pins.

expert reply by: Jeffrey L