Need some wiring help :)

[Davcos]

Alright so I'll try to explain this the best I can, can add pictures tomorrow if needed. I bought a new license plate light that also has a 3rd brake light built in. I was going to avoid cutting into the OE wires on the truck so the plan was to wire it in with the hitch harness since I never tow anything anyways. The license plate light is wired into the existing wires so that is taken care of, the minor problem I have right now is with the 3rd brake light. I have the hitch harness plugged into the truck and cut the other end off which left me with 4 wires (green,brown,yellow,white)
Right now I am using green & white, everything works how it's suppose to except for when I put on my right signal the 3rd brake light also flashes with it. Since the LEDs are fairly dull I do not mind it like this but with it only doing it for one singal it looks dumb, I need to figure out how to either make it not flash with either.. or to make it flash with both signals

 

[Prime]

Okay. So.

Quick graphic on the the 4-pin trailer harness.

So. When you press the brake pedal, the trailer circuit fires up both the left and right blinker circuits to constant voltage. That creates the brake lights. When you use the turn signals, it simply alternates one of those.

This is why it blinks. Now. If you tap both signal wires to the brake light, then it'll blink on either signal and SHOULD stay solid on the brake.

 

[Davcos]

Alright thanks for the diagram, I'll mess around with it tomorrow

 

[Ghettomedic]

Use caution when tapping both wires though, it may back feed to the opposite light.

 

[metzican]

It should be designed to work the way Prime said it will. You are essentially wiring up a trailer without the turn signal feature. I know you can buy those little brake lights that go into a 2" hitch and they act as a 3rd brake light. These just plug into the trailer harness and this is the way that it works.

 

[Davcos]

I put both signals to the brake light and it made them both flash. This light has the following wires, green(tail/license plate light), (red) brake & (black) ground. I have it set up as follows

Light mount.......... Trailer wiring
black (ground).......... -white (ground)
red (brake)............... -yellow (left signal)
green (tail/license)....... -brown (tail lights)

I'm pretty sure that is how its set up right now.With this setup everything works how it should but the 3rd brake light does not flash with right signal. when I tapped right signal into red(brake) it made them both flash at once. This isn't designed to flash with the signals I just thought it would be cool if it did, maybe i'll have to just forget that idea unless their is an easy fix