Troubleshooting Install of Prodigy P3 Brake Controller 90195 in 2017 Ford F-450 Cab & Chassis

Question:

I am having trouble installing this brake controller. I found the wiring harness behind the dash. The adapter I bought fits it perfectly. The issue is that when I plug the controller into it the screen flashes very rapidly but does not display anything. Then after a few seconds of that all of the guages on the dash stop working and then every possible indicator light in the instrument cluster comes on. If I unplug the controller it all goes back to normal. I have checked all fuses. I have also made sure that the rear trailer plug is giving out power correctly. Not sure what else to do.

asked by: Justin C

Expert Reply:

Wiring adapter # 22292 is the correct one for installing a Tekonsha brake controller such as the Prodigy P3 # 90195 in your Ford F-450 cab and chassis.

There are two possibilities you can check to troubleshoot this issue. First, use a circuit tester like # PTW2992 to confirm that the connector under your dash has one pin with constant 12V power and one with 12V power ONLY when the brake is pressed. The other two pins should not carry any voltage. If your vehicle connector displays different signals it may not be the right one.

The other thing to check is that your wiring adapter # 22292 is pinned-out correctly. It is rare but it does happen that one or more of the four wires on the wiring adapter could be connected to the wrong pin. The correct configuration is that +12V constant power should reach the P3 on the black wire; the brake pedal switch signal should reach the controller on the red wire; white is ground and blue is output to the 7-way. Make sure this is how the signals are reaching the P3.

You can also refer to the linked articles for additional guidance.