Troubleshooting a 12 volt Power Circuit on a 2006 Ford E350 Van

Question:

Hello, I am adding work lighting to a trailer pulled by a Ford E350 Van, 2006 model. All of the pins on the factory trailer wiring connector are working except for the 12 vold Aux terminal. All fuses seem to be OK. Am I missing a switch that powers this terminal up? What should I be looking for or do to get power to this connecter pin?

asked by: Mark M

Expert Reply:

It sounds like a fuse has blown somewhere on that circuit, but since you checked that already you might try checking the back of the 7-way to see if the circuit is connected to the connector properly. There could be corrosion there that is causing the circuit to short out. You might use a circuit tester like our part # PTW2993 to check for voltage behind the connector and then work your way up the circuit looking for voltage to see where the problem lies and fix as necessary.

Since you said you checked the fuses you might also check the relays. Typically these are in the fuse box as well.

Check out the picture I attached, it shows the trailer wiring connector wiring and which wire is the 12 volt power wire to help you test the circuit.

expert reply by: Jameson C