posted this on another forum, but nobodys had any advice. Hope to have better luck here?


Wiring up a HD Modulite to hopefully prevent any problems

Also found a cheap factory harness so I could hopefully prevent cutting into the factory harness and/or lights.


Factory harness I found features the two plugs as shown and than branched off into a 4 prong trailer harness.

Cut the 4 prong harness off, wired the trailer side of it into the harness I purchased and than wired the vehicle side of the Modulte into the female side plug to connect to the factory harness where I disconnected it where it goes into the 7 pin factory harness.


Question if I should ground the red wire on the tow vehicle side of the modulite or should I splice it in somewhere?

Notes say to ground red wire in a 2 wire system

3 wire system attach red wire to vehicles stop lights



(SO... if you've done one of these or know more about it than I do, which isn't much, please chime in)

 

Sorry to pick up this thread so late, but I'm now trying to figure out the same thing. The Dodge Ram would appear to be a "3-wire" (separate stop and turn bulbs) system, and the Modulite instructions call for you to hack into the rear light wires. But if you don't want to do the latter, opting instead to connect at the factory trailer wire plug, it would seem that it has already been converted to a 2-wire system. Therefore, it would seem, you should ground the red (brake) wire from the Modulite like it was a 2-wire system.

Please tell me what your experience was hooking up the Modulite this way.