Troubleshooting Brake Controller That Triggers Warning Lights on Mazda CX-5

Question:

Hello, Regrettably, I had my local mechanic install the 4 pole and 7 pole wiring to my cx-5, along with the Prodigy p-2. All the wiring is working properly except the brake controller. When the braking unit is powered up, error codes flash on the car dash for the braking system. It appears everything is wired correctly....If the unit is unplugged, all other functions operate normally. What are we missing? Thank You,

asked by: Rick E

Expert Reply:

If installing the Tekonsha Prodigy P2 Brake Controller # 90885 triggered error messages on the dash of your 2018 Mazda CX-5 then most likely the red wire from the controller was connected to the wrong wire on the vehicle. The red wire (brake input) should be connected to the cold side of the brake switch behind the brake pedal. This will be the wire that ONLY receives power when the brake pedal is depressed and no power with any other function.

It is very important to use a circuit tester like # PTW4993 when making this connection to ensure you find the correct wire.

If this does not resolve the issue please let me know and I will be happy to look into this further.

expert reply by: Chris R