Wiring rear light to old trailer brake wire ???

[BullElk]

Thought I would run this scenario by whomever may care to read. As shown in pics below, shouldn’t I be able to use this existing trailer brake setup to wire into reverse lights or something else I may choose?

This is where all wires come to connect to trailer brake switch...

One wire is to battery positive....

Another is connected to a very small wire coming from a box above left foot wall....

Another is going back to rear of vehicle and another is grounded under dash.

 

[BullElk]

Ok den....

I see that the red wire in picture is spliced to the brake light for previous trailer brake purposes. Where would one go to find out which wire is the reverse light? Would just wire color be accurate? Anyone have a handy wiring diagram in your pocket ?

 

[Njck22]

Assuming that's spliced into the Body ECU, with the goal of getting the brake light signal, the wire color should be green with a white stripe.

 

[BullElk]

That was the goal when previous owner hooked up trailer brakes. Now I am trying to use the existing setup to splice into additional reverse lights I have. So I am trying to figure out which wire is for reverse lights so that I can splice into it like PO did to brake light wire.

 

[Njck22]

apologies, misread your question.

For a reverse signal, It does not seem to interface with the body ecu at any point. (I'm looking at a 2007 EWD, a glance at a 2004 Diagram looks to be the same as well.) Depending on which LC you are working on, you could get the reverse signal from the navigation ecu, television camera ecu,(both under passenger seat) or the park/neutral position sensor (goes into the transmission). could also splice from the wires going into the reverse lights at the back, this would work on any vehicle and probably be the least invasive. Color will be Red with a black stripe(R-B)

 

[BullElk]

Thanks for the information. I already have one wire (trailer brake wire) going to the rear, but only one. I guess I would need to run another wire to the rear to splice into two wires for each light. I was trying to eliminate that option if I could splice into the body ECU like PO did. Well, I guess its good that half of the wiring is already completed.

I have already spliced some very bright LEDs into the reverse wires. Last night sitting at a redlight, a car was behind me with their brights on. I put it in reverse to show them how I feel. They quickly clicked theirs off. Now I want to be able to do that with a toggle switch on demand.

Thanks for your time Sir.