Location of Fuse that Controls Trailer Lighting on 2013 Ram Diesel

Question:

Is there a fuse or relay that will stop all trailer lightsand trailer breaks from working. On a 2013 dodge ram 6.7 cummins?

asked by: Timothy Y

Expert Reply:

If the trailer lamps aren't working, you'll first want to determine if the cause is with the vehicle or with the trailer. Use a circuit tester like # PTW2993 to check the pins on the trailer connector while somebody activates each lighting function. If you get signal on the pins, then the problem lies with the trailer, and not the vehicle.

With no signal at the pins, then unplug the wiring harness from the rear of the 7-way trailer connector, and test the pins on the socket. If you get signal there, then the 7-way is bad and should be replaced with # HM40975. Sometimes the factory harness reaches a rectangular connection about a foot rearward from the 7-way. Unplug that connection, and test. If you get connection there, replace both the 7-way and the short harness using # HM40975-11933.

If you still find no power, take a look at the fuse in position # J14 in the main fuse box, which Ram refers to as 'Trailer Tow and Park Lamps'. It should be a blue 20A fuse.

expert reply by: Mike L