How to Install a Universal Trailer Tail Light Wiring Harness on a 2006 Dodge Ram 1500

Question:

Questions about the best way to wire the Modulite to the factory Dodge tow wiring with 7 blade round plug. One of your prior posts suggested that this vehicle, is a 2 wire systemfoot correct? So wires going into the Converter: The green wire would tap into the right turn signal wire of the truck, the yellow into left turn, the brown into the running light circuit and the white and red wires would both be grounded to the vehicle frame right? And, I ran the black wire to the battery with a fuse, from your kit. Is the above correct for my vehicle? Question #2 regarding the plug. I now have the 4 wires to deal with at the Modulite plug: brown, yellow, white, green. I assume I cut off this 4 pole plug because these 4 get wired into the 7 pole truck trailer plug. But, what existing wires do I LEAVE ALONE at the 7 pole plug and which ones would I literally cut from the the existing 7 pole plug if any, OR do I splice into respective wire at the plug? I assume I leave the 7 pole electric brake, black battery and auxilliary wires intact. I also assume the white wire from the Modulite 4-wire plug could be spliced in to the white wire of the 7 pole. Should I cut the existing plug wire and substitute, or just splice in: yellow left turn, green right turn, and brown tail lights? OR......?

asked by: Michael

Helpful Expert Reply:

Your 2006 Dodge Ram 1500 actually has the separate tail light wiring system, meaning the turn signals and the brake lights run on separate wires. The tow package wiring will have the combined-wire setup, but if you are installing the Universal Wiring harness, # C59496, to bypass the factory tow package wiring, then you will want to follow the instructions for the separate (3-wire) system installation.

This means the Yellow wire goes to the driver's side turn signal, Green to passenger side turn signal, Red to brake light wire, Brown to tail lights and white to ground.

If you are bypassing the factory tow package wiring, then you will want to cut off the 4-pole connector as you said and cut the taillight wires going into the 7-way trailer connector. You will not want the factory tow package taillight wires still connected to the truck's 7-way trailer connector except for the ground wire, you can just splice that in.

To determine which wires are the correct taillight wires on your factory trailer wiring, I recommend using a circuit tester, like part # PTW2993, while a helper runs through the taillight signals in the truck. Just probe each wire until you determine which wires carry which functions. I do not recommend splicing color for color as there really isn't an industry standard color code and vehicle manufacturers have been known to change wire colors over the years.

expert reply by: John H