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How to wire car hi-beams to additional switch that controls off-road LED bar

Rainlord

Aug 18, 2017
1
Joined
Aug 18, 2017
Messages
1
Hi,

I have an electrical module for my car (see link, it consists of a button-bar of 8 buttons and a wiring harness) that lets me wire up additional lights to that I control with said buttons. With this I've done some wiring that lets me turn lights on and off. The wiring harness for this is quite simple in that the buttons connects to the harness, then it has 8 red wires that each represents 1 of the 8 buttons, and when a button is turned ON the wire has power, when it's OFF the wire has no power. But for me I'm now beyond my wiring skills.

Here's what I want to do:

The cars hi-beam switch should do exactly what it does now, meaning it turns on/off the high beams at all times. As it does that so, the cable that goes to the high-beam lights either has power or doesn't. Pretty straight forward. It undoubtedly goes via a relay that I cannot access, but I can access the wires from it to the light.

One of my installed components is a LED light bar. I had this wired to a button, which is easy as its power-in cable is one of the 8 wires for the buttons.

However, what I want instead is that; when one of the buttons in the car is turned ON, the high beams being turned on should also turn on the LED bar. When the button is OFF, the high beams act just like they do normally (on/off), but the LED bar stays off. Then, as a rather necessary feature, I would like one completely separate button to turn on the LED bar by itself so that I can operate it without the need for high-beams being on, should I want to.

In short, here's all combinations and their desired results:

Button "HIB" = button for LED bar to be turned on/off with hi-beams.
Button "LED" = controls only LED bar on/off.


Button HIB OFF. Button LED OFF.
Hi-beams on = LED bar off.
Hi-beams off = LED bar off.

Button HIB ON. Button LED OFF.
Hi-beams on = LED bar on
Hi-beams off = LED bar off

Button HIB OFF. Button LED ON.
Hi-beams on = LED bar on
Hi-beams off = LED bar on

Button HIB ON. Button LED ON.
Hi-beams on = LED bar on
Hi-beams off = LED bar on

I can't quite wrap my head around the wiring and would love some help. I have a feeling it's easier than I make it sound. I've drawn up a rough wiring diagram of how it currently looks (I've omitted ground and negative wires as they always go to either the chassis of the car (ground), or the negative terminal on the battery).

I assume wire H1 has to go through a new relay together with wires T1 and S1 but I don't know how.

VZa5xWz.jpg


Here's a picture of a typical car relay and how it functions, it has 5 pins at the bottom that you can connect to.
RelayWiringGuide.jpg


Huge thanks in advance for any help!
 

kellys_eye

Jun 25, 2010
6,514
Joined
Jun 25, 2010
Messages
6,514
Wire a diode from the 'together with hi beams' button straight to the 'controls LED bar by itself' line.
 

Bluejets

Oct 5, 2014
7,050
Joined
Oct 5, 2014
Messages
7,050
Assumption on how high beam system operates is incorrect if you vehicle is anything up to 20 years old and after that, Nissan among others. Google " negative switching lights 4x4 dot com." There are diagrams there for both systems.
 
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