Troubleshooting Tekonsha Sentinel Brake Controller Malfunction

Question:

The green and red lights on the face of the controller are on even when the truck key is off.

asked by: Larry

Helpful Expert Reply:

Although newer controllers have a 'sleep mode' they enter into after 15 minutes or so of inactivity, the Sentinel should show no lights if the brakes aren't being applied and there is no trailer connected.

The standard troubleshoot would be to disconnect the blue wire exiting the rear of the controller by cutting it. Be sure to leave enough room to reconnect the wire. If severing the blue wire makes the lights go off, you have a short somewhere in the brake output circuit between the brake controller and the trailer connector. A damaged or corroded trailer connector is a frequent culprit here. If you can see any green or white corrosion on the blade terminals in the trailer connector, there's a good chance the corrosion has spread internally at which point you'd want to replace the 7-way. Part # PK11893 would make a good replacement.

You can see an installation video by using the provided link.

If cutting the wire doesn't fix it, disconnect the black power wire for a few minutes. The Sentinel has an internal microprocessor which can sometimes have issues that can be reset by turning the controller off for a few minutes. If that fails to get the lights to go out, then the controller is faulty and would need to be replaced.

The Tekonsha Primus, part # TK90160 would make an excellent replacement, you'll also need the # 3025-P wiring harness if you don't already have one that plugs into the junction box under the dash behind the emergency brake pedal.