High Beam Trigger: Solved.. plug and play

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baja-chris

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Why not just trigger them from your factory fog lights using the NC pin of a double throw relay?
Turn fogs on. Then when you go to high beams your fogs automatically go off and your off road lights go on. And vice versa.
Fogs should be a factory halogen not led, so just a 12v wire. Power the off road lights from an upfitter switch so they can be enabled or disabled in case you want headlights without fogs and without off road lights. No need to mess with CAN Bus.
 

baja-chris

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If factory fogs are not halogen then what are they? I threw mine away after replacing with BD so I can't look at them to see.
Anyway the point is the fogs are not controlled with the CAN Bus like the headlights are and so that circuit can trigger a relay to automatically have off road lights come on/off with high beams.
 
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aR4CE

aR4CE

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If factory fogs are not halogen then what are they? I threw mine away after replacing with BD so I can't look at them to see.
Anyway the point is the fogs are not controlled with the CAN Bus like the headlights are and so that circuit can trigger a relay to automatically have off road lights come on/off with high beams.
The Factory fogs are led, but that is another way to do it- there is a +12V that could be pulled from them and use reverse logic when they shut off.

I, as many do, enabled fogs with high beam via forscan. During normal day to day driving, I disable the XL linkable via the aux switch, so normal high beams plus fogs is a nice to have.

Just another way to remove the skin from a cat. This method gives the greatest amount of control and I believe is more OEM+.
 

shigman

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So are there relays that use reverse powered on logic for activation. You'll have to excuse the noob question, Ive only wired relays that rely on powered on.
 

baja-chris

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You just need a relay that has both a NC (Normally Closed) and a NO (Normally Open) pin. Connect the off road lights to the NC if you want them on when the relay is not energized. Then when energized (fogs on), the off road lights go off. If you use the NO pin then it would behave like a common relay that does not have the NC pin.
 
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