Troubleshooting Brake Controller that Doesnt have 12 Volts on Red Wire when Brakes are Applied

Question:

just installed with the trailer harness kit and controller adapter on 2004 wrangler. trailer not connected at this point. dont have red dot when brake pedal pushed. brake lights work and have red light when manual button pushed. test light in blue wire does not give load when pedal pushed. test light in red wire does not light up with pedal, but does when button pushed i am on correct wire at pedal and appears to have connection with the wire splicer. what am i missing?

asked by: Sands R

Expert Reply:

The red wire of the controller needs to be showing voltage when you apply the vehicle brakes otherwise the controller is never going to activate when you apply the vehicle brakes.

You need to verify the circuit you are trying to connect that wire to has 12 volts when the brakes are applied. Issue could also be the connection isn't being made completely and you'd just need to make the connection better.

expert reply by: Jameson C