Wiring LED Brake Light Bar

Hi All- 1st question to the forum so play nice Have a 2013 SR5 DCSB. I bought a rampage LED brake light bar a few months back as the black brake lights from the prior owner are too dim (for my comfort). I've added a brighter, black 3rd brake light, but better safe than sorry / getting rear ended. It's currently plugged into the 4 pin harness as shown below, but it looks slapped on instead of a clean install. Simply doesn't look good.


The install instructions only reference using the 4 pin, with the option to splice the white (reverse) wire into the brake lights positive wire. So I've tried looking at wiring diagrams, and honestly it looks like gibberish to me, or advanced mathematics . Could someone please help translate this into the basic colors I need to splice? Based on my other searches it seems that the whole rig can be spliced on the drivers side brake light, yes?

 

Welcome!! Give me a few minutes and I'll see what I can find for you.

 

Sweet. I don't mind the wiring, having done a number of stereo's - but those have a wiring harness which makes it about as easy as painting by numbers.

 

The functions for the wires in the factory tow harness are:
White - Ground
Red - Left Turn (will also come on with brakes)
Brown - Right Turn (will also come on with brakes)
Black - 12v (this is the constant hot wire it will only be on when the ignition is on)
Blue - Electric Brake
Yellow - Reverse Lights
Green - Tail Lights

Since you have the factory hitch, you can splice into that.

 

So I know the Rampage white line is "reverse" and splice that into yellow.
I just need to determine the green/yellow/red lines and splice in accordingly, correct?
Should I splice in before the wiring gets to the hitch, or after, or does it matter? Didn't seem like a lot of room to work when I got under there a few minutes ago.

 

I havent looked under mine so I can't say 100%, but you can splice anywhere in there where it's convenient. You are correct about just matching the wires to each other. For your specific light, did it come with a wiring diagram?

 

No diagram or anything I see on their site. I'll contact them and update the post once I have that info.

 

http://graph.darren-criss.org/2016/02/03/gmc-trailer-plug-wiring-diagram-l-55179096c511ba08.jpg

All the diagrams I'm looking at for 4 pin show the same thing.

Green-Right turn and brake
Yellow-left turn and brake
Brown-taillights
White-ground

Are you sure the white one is to be spliced for reverse? It seems weird they would include it in the plug. From what I've seen on other ones. it's a 5th wire, that's loose.

 

Correction. Just looked at the instructions and diagram was hidden in plain sight - top of the page!

Right to Right
Left to Left
Ground to Ground
Reverse to Reverse

? Running lamps to... Green Tail lights?

 

Yep!! That's exactly right.

 

Sorry- white is the reverse line on the rampage, which is color for Ground on the tow harness.
Rampage white to Tacoma yellow...

 

Since the colors don't quite match up, I recommend using some painters tape and labeling each wire on the rampage. It'll help make it a bit easier.

 

Good idea. This'll be my project for the weekend, with an update when completed.

 

Sweet! I'm excited to see it all work out.

 

Depending on which way you are going to wire this... my suggestion is to buy a "vehicle side" trailer harness pigtail and wire that into the hitch harness. you will need to solder the connections. if done right, it would look stock and will give you a 4 pin plug to plug into. i have done this on many vehicles.

assuming nothing has changed for the 12+, the trailer 7 pin socket harness can be disconnected at the connector located just above the hitch on the truck frame. this makes it easy to remove and to perform the work off the vehicle.

 

Good info fergyz. I wasn't sure on the disconnect, so just unscrewed the hitch assembly to have some room to work. Still added a lot of extra effort to do this on the ground, particularly with a sore back.

Used wire connectors splicing in the LED bar and the re-wrapped the assembly.


I did have a moment of concern when I had most, but not all, of the connections completed and none of the functions worked when I tested them. Once everything was connected all functions and reverse lights are working great.


Really appreciate the help guys!

 

Hell yeah man! That's what I like to hear. Congrats