Troubleshooting Curt T-Connector Wiring Kit on 2015 Ram ProMaster City

Published 06/28/2022

Products Featured in This Question

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

(52)

$100.05

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

(43)

$66.72

Question:

I installed the wiring harness last summer to pull a vacation trailer. It all worked beautifully. I stowed the trailer and have not used it for a year. When I hooked it up to test the lights I am having the following problem. The left trailer light is on constantly. The left turn signal does not work. The right turn signal works fine. When I hit the brakes, the right light comes on normally, but the left light goes out. It comes back on when the brake pedal is no longer depressed. The running lights work fine when the van lights are on. Is this a wiring problem or could there be a problem with the control module. Any help would be appreciated. PS. I have a tester and it acts the same with the tester and the trailer.

asked by: Mark P

Expert Reply:

If the Curt T-Connector Vehicle Wiring Harness # C56270 on your 2015 Ram ProMaster City is sending those same signals whether your trailer is connected or you're using a circuit tester to check functions then it likely means the Curt wiring is bad if the lights on your ProMaster City are acting normal. You can verify this by testing the wiring going into and coming out of the Curt control module. If the wiring going in is operating properly but you get that abnormal operation on the output end of the module then that's where the problem lies.

To replace the Curt wiring kit I recommend picking up the Tekonsha T-One # 118719 which we have found to be more reliable when it comes to the operation of the module.

Attached are some installation videos for you to check out.

expert reply by: Jon G