Troubleshooting Malfunctioning Brake Controller and 7 way on a 2002 Ford F-150


I have a 2002 Ford F150 supercrew with factory tow package 7 way & 4 way. I installed a brake controller Hopkins Agility and adapter pigtail. Plugged it into the factory plug under the dash. Break controller indicated there was a trailer connected when there was not. Checked the 7way, it had water in it. Dried it out, checked trailer brake contact in 7way plug, test light was faintly illuminating. Checked with volt meter, it showed 4.5 volts on the trailer brake leg of 7way plug. I dont think there is supposed to be any power on the trailer brake leg of the plug, when the brake controller is in standby mode, vehicle off, and no trailer attached. When you press the manual override switch, the brake lights on my truck come on. Is that normal? Brake controller is not displaying an error message. I am thinking I have a defective brake controller. Any advice will be greatly appreciated. Thanks in advance.

Expert Reply:

My first thought is that the water has corroded some of the connections inside the 7 way port and something is getting crossed. The connections inside the plug are fairly close together so water damage could be the root cause. I would replace the 7 way with either part # 118242 or part # 30955 depending on how the factory wiring is done. It would be a good idea to clean the connectors on the truck, and use some dielectric grease like part # 11755 to protect the connectors from future water damage and corrosion.

It is possible that the brake controller was set up wrong or is defective. Using the installation instructions for the brake controller, set up the brake controller from the beginning making sure to adjust the power levels of the controller. Brake controllers should not go bad right away as they are made to provide years of service.

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