How to wire a trailer light hookup
How to wire a trailer light hookup
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From: Virginia
The plug should be labeled when you take it apart. Find the wiring in at the rear of the truck on the driver's side.
You should have a brown wire. This goes to the running lights. Trim the insulation back and wrap another wire around it and solder it. Tape it up and hook this wire to the running lights connection on the plug.
I am not positive about the color of the brake/turn wires, since the diagram I have is not very good. They show a green for the passenger side rear, and a yellow/black for the driver's side rear. If you turn the signals on, the correct wire will have voltage going up and down on it. Splice these wires to the left and right brake/turn terminals on the plug.
The plug also should have a terminal labeled GND. Hook a wire to this terminal and then bolt the other end to the frame.
That should take care of the lights, unless you have back-up lights on your trailer.
You are then going to have to buy a brake controller. Mount it under the dash, and go buy a 20 or 30 amp circuit breaker. Mount the circuit breaker on the inner fender over near the battery. Run a short piece of 12 or 10 gauge wire from the bat + to the circuit breaker. Then run another piece of 10 or 12 gauge wire into the cab from the other side of the circuit breaker, and hook it to the controller like the instructions say.
Hook the other wires up to the controller(the brake switch, etc.) per the instructions, and also the 12 or 10 gauge wire that goes to the brakes. This wire will run back out of the cab, down the frame rail, and hook to the plug that is labeled "brk".
The above is the minimum you need to pull a heavy trailer. There are other pins on the 7 prong plug you can use for different things, but it depends on what kind of trailer you are pulling.
You should have a brown wire. This goes to the running lights. Trim the insulation back and wrap another wire around it and solder it. Tape it up and hook this wire to the running lights connection on the plug.
I am not positive about the color of the brake/turn wires, since the diagram I have is not very good. They show a green for the passenger side rear, and a yellow/black for the driver's side rear. If you turn the signals on, the correct wire will have voltage going up and down on it. Splice these wires to the left and right brake/turn terminals on the plug.
The plug also should have a terminal labeled GND. Hook a wire to this terminal and then bolt the other end to the frame.
That should take care of the lights, unless you have back-up lights on your trailer.
You are then going to have to buy a brake controller. Mount it under the dash, and go buy a 20 or 30 amp circuit breaker. Mount the circuit breaker on the inner fender over near the battery. Run a short piece of 12 or 10 gauge wire from the bat + to the circuit breaker. Then run another piece of 10 or 12 gauge wire into the cab from the other side of the circuit breaker, and hook it to the controller like the instructions say.
Hook the other wires up to the controller(the brake switch, etc.) per the instructions, and also the 12 or 10 gauge wire that goes to the brakes. This wire will run back out of the cab, down the frame rail, and hook to the plug that is labeled "brk".
The above is the minimum you need to pull a heavy trailer. There are other pins on the 7 prong plug you can use for different things, but it depends on what kind of trailer you are pulling.
Last edited by Franklin2; Feb 1, 2007 at 07:12 PM.
