Brake Controller Shows it is Connected but Display Doesn't Change when Stepping On Brakes

Question:

Brake controller shows connected but does not change when brakes are applied. .c

asked by: Connie B

Expert Reply:

Are you doing this test with the vehicle sitting still? If so that would be why the display doesn't change when you step on the brake pedal. The P2 # 90885 and other brake controllers send power back when it senses deceleration and you step on the brake pedal. If you are sitting still it won't send power back unless you use the manual override.

It is also possible that the gain or power output is set too low. Use the wheel on top to adjust power output. Rolling it towards the front of the vehicle increases power.

If the controller is tilted or turned to the side that can affect how the controller senses movement and that could be the issue.

Also check the connection at the red wire. The red brake controller wire should have power on it when the brake pedal is pressed. If it does not then the red wire is either connected to the wrong wire on the vehicle or the stop light or CHMSL fuse is blown on the vehicle.

expert reply by: Michael H