Brake Controller Works When Manual Override Is Pushed But Not When I Press Brake Pedal
Updated 09/12/2025 | Published 08/17/2025
Question:
My brake controller light is on and the brakes work with the manual slide, but not with the pedal, or at least the light isn’t changing colors. The brake lights are working could it still be my switch or would it likely be the controller? I still need to test the wire coming from the switch to see if it has power when I press the pedal.
asked by: Chris H
Expert Reply:
Hey Chris,
Are you testing this while you are parked? The controller you are asking on is a proportional controller, meaning it sends power to the brakes based on deceleration when you hit the brake pedal. If you are testing it while parked it's not going to send anything back when you press the pedal, but it always will when the manual override is pressed.
Another possible issue found in older Chevy's is the stop light switch int he vehicle going out. If you press on the brake pedal and the vehicle brake lights come on that is not the cause, but if you step on it and they do not come on you would need a new stop light switch.
If the issue is during travel than it is going to be an issue with the brake input circuit (red wire) and reconnecting that wire usually fixes the issue. If that does not work let me know and I can continue to troubleshoot for you.
Nick S.
9/12/2025
Hey Chris, did you have a chance to test the wire from the switch to see if it has power when you press the pedal? If you're still experiencing issues, I'm here to help troubleshoot further.