Hooking up an aftermarket gauge, and it calls for the 12V power source for it's light, from either the headlight switch or headlight switch fuse.

I cannot seem to find the fuse that powers the headlight switch, and I can't find a wiring diagram for the headlight switch plug, which has tons of wires in it.

It cannot be sourced from a dimmable light wire (i.e.: shifter console lights), as it may not get enough volts to operate the gauge correctly.

Bottom line, just looking for a constant light source to tap into on the headlight switch (correct power wire) or where the headlight switch draws its main power from.
07 H2

 

Is the power for the whole gauge or just the backlighting on it?

I would run the wire through the firewall to the under hood fuse box and find something that uses switched ignition power(ie: climate control, drls, etc…) and install a normal fuse tap from the auto parts store.

there’s also a box under the dash by the pedals where connectors go. One of those pins should be switched ignition if you have a multimeter to test. You could use a butt connector and slide it over one of those pins and run it to the gauge. I have done this before too.

The gauge shouldn’t draw much power so really anywhere would be safe.

 

 

4 wires total.

yellow: 12v Constant Source (+)
Red: 12v Ignition Switched Source (+)
Orange: 12v Headlight Switched Source (+)
Black: Ground (-)

I did tap into the in dash fuse box for the ignition switched Red wire, Yellow constant source and ground wire, and I'll use the wiring diagram for the headlight source Hummerz posted. Thanks