7 PIN TRAILER WIRING MANUAL

Check for loose splices and cut/chafed wires from the brake drums to the trailer connector.Each magnet has two wires coming out of the brake drum - 1 wire should be connected to the trailer brake control (often, but not always a blue wire) in the wiring harness while the other needs to be connected to a good ground (typically the trailer frame). Each individual trailer brake contains a magnet that engages the brakes with a force proportional to the voltage supplied by the brake controller.If the brake control pin on the truck's connector reads 0 volts while the brake pedal is depressed, the problem is likely the brake controller and/or wiring between the controller and the truck's trailer connector.

The voltage supply to the trailer brake pin on the truck's connector should read a voltage that rises as the brake pedal is depressed further and further, and should read 0 volts when the pedal is not depressed. Have a second person press the brake pedal while you read the multimeter.Use a digital multimeter to probe the brake control pin on the truck connector (see diagrams above for 6 and 7 pin connectors).Verify that the trailer brake controller is powering on.Verify the trailer brake controller is functioning Check for chafed, exposed, or cut wires and loose electrical connectors along the trailer's wiring harness. If you have confirmed that the problem is not with the tow vehicle and verified that the connection between the truck and trailer is solid, the problem must be with the trailer.

7 PIN TRAILER WIRING MANUAL

Refer to your owner's manual for information regarding specific fuse locations. If the pins are not providing power when they should, check for blown fuses and/or chafed wires along the frame.If the appropriate pin reads ~12v+ with the switch/pedal engaged, the problem is with the trailer, not the truck.The pin should read 12v+ when the corresponding light is activated from the truck. With a digital multimeter set to the proper range to read ~12v+ (or using a test light), probe the appropriate pin and a good ground (clean area on the frame, bumper, etc).have someone depress the brake pedal, activate the turn signal, etc. Have a helper operate the light(s) that are not working, i.e.

Disconnect the trailer connector from the truck.

If the connector has no ground, the ground wire has been cut, disconnected, corroded, etc find and repair as necessary.ĭetermine whether the problem is with the truck or the trailer.

If the connector has a good ground, this is not the problem.

Using a digital multimeter, check for continuity between the truck's ground pin and the chassis (probe the ground pin of the connector and a clean spot on the frame/bumper).

If no lights are working, check the ground at the truck connector If this does not remedy the problem, continue to step 4.

Replace the bulb or light assembly, the most likely problem is that the bulb has burnt out.

A shot of WD-40 or dielectric lubricant into each of the connectors may help clear and clean the connectors.

Clean any dirt or debris from both connectors and ensure that the trailer connector is inserted completely into the truck connector.

Check the connection between the truck and trailer

7 pin trailer wiring