No Trailer Brake Function After Installation of Brake Controller

Question:

I bought a 2004 dodge ram took to shop had brake controller hooked up he wired hot wire to an grd wire to contriler an ran blue wire to the 7 plug 4 the trailor brakes an all the 10 yrd of work an said I was good to go so I hooked up to go camping all the lights an turn signals work but when I set the number on the controller for 30 the number light went off ater I set it I thought that was normal I reset it later at 40 same thing lihjt went off so is the controollworking but dont feel camper brakes being actinging at all thanks

asked by: Jim

Expert Reply:

The method for installing a trailer brake controller like the Tekonsha Prodigy P2 # 90885 in a 2004 Dodge Ram will vary depending on how the truck was equipped from the factory. It does sound like your truck had no factory trailer connector and that the controller unit was installed by hard-wiring.

You can test your 7-way to see if the brake controller's output is reaching it. Disconnect the trailer and have a helper activate the controller's manual override. With a circuit tester like # PTW2993 ground the negative probe to the pin at the 7-o-clock position and apply the positive probe to the pin at the 5-o-clock position on the 7-way (please see the red arrow in the linked photo). You should detect the controller's output signal on the 5-o-clock pin. If there is no signal, then there is an issue with the controller itself or with the vehicle wiring. Make sure the controller's ground connection is solid; a weak ground could prevent the brakes from getting enough current to activate.

I have linked two articles on brakes controllers that will help you troubleshoot.

You can also test your trailer brakes by directly applying +12V power from a battery (the one in the vehicle or a spare) to the pins on the trailer's 7-way plug. If the brakes work when activated in this way, then you know the problem is on the vehicle side.

expert reply by: Adam R