Troubleshooting Curt Spectrum Trailer Brake Controller Green/Red Light Intermittent Issue

Updated 10/03/2022 | Published 10/01/2022

Question:

When I let of the brake a light will intermittently remain on on the controller. Sometimes it is a red light sometimes a green light. It will stay on until I tap the brake pedal. If I shut the truck off for the night and don’t notice it is on, it will still be on in the morning. Is there a problem with my controller?

asked by: Eric W

Expert Reply:

With the red or green light remaining on your Curt Spectrum Trailer Brake Controller # C51170 after you have released the brake pedal you likely have one of two issues with your device. The light will remain on as green or red when it detects a short in the red wire to ground. You will want to trace the wire to determine if it has rubbed itself on a metal surface and is now shorting to ground. It may also be a loose connection inside the connector so be sure to check any plug and play or butt connectors depending on your application. It should also be noted that if the brake switch the controller is connected to is faulty this would also cause the issue so you may need to have it tested at a service center.

If you do not have any of these issues the controller could also be experiencing a short inside the controller itself. As it is an intermittent issue it is often difficult to bench test this with a controller and get it to duplicate. The installation instructions are listed below and offer the wiring diagram along with instructions on bench testing the controller.

expert reply by: Bud M