Troubleshooting No Brakes With Prodigy P2 Brake Controller

Updated 12/20/2021 | Published 12/17/2021

Question:

2004 Dodge ram 3500. Controller has been in vehicle forever, One day hooked up trailer and brakes didnt work. No indication on controller. tested lights on trailer, all good. tested wiring at controller, white- grnd., red -hot during braking, black - 12v allways, blue- no voltage when trailer is not connected. but when trailer is connected blue wire is hot, still no brakes on trailer.

asked by: Paul

Expert Reply:

It sounds like you have already gone through a lot of steps to check your Tekonsha Prodigy P2 Trailer Brake Controller # 90885. From what you have said it sounds like the controller is functioning properly based on the wires you checked.

If you have not already done so, I would start by checking your 7-way at the back of the vehicle. Make sure it is clean and no corrosion is present. I would also check the connection just like you checked the wires at your brake controller. If everything is functioning properly the problem is the trailer and not your brake controller or vehicle wiring.

If you find that the 7-way is not working properly on the vehicle side, start by checking your ground connection. It should be on a clean, bare-metal surface. From there you will be checking for a short in the wiring.

If it is on the trailer side then I would check the wire running to your brakes for a short. Again, check the ground connection as well. More than likely this is the problem if everything else checks out.

You may also want to make sure your brakes are adjusted assuming they require manual adjustment. The last thing you could check is the brake magnets.

I have attached a helpful article on troubleshooting brake controllers which also covers brake adjustment and another article on testing brake magnets for your reference.

expert reply by: Robin H