Hi everyone,

I have the electrical manual, but I’m uncertain which wire to splice into for an add-on gauge (oil pressure) so the gauge dims when the headlights are on in order not to be too bright at night.

My best guess is the “Headlamps - Dip Beam Operation” wire, which is blue/red (color code: UR). Is this the correct wire?



Or am I supposed to use a wire for the dash lighting that dims when the headlights are on? Ideally the gauge lighting would be adjustable, linked and and controlled by the main dash lighting rolling dimmer that’s on the steering column. I don’t know if that’s what I tap into and if that wheel has multiple wires on it, which one I’d use.

I was also told there is a dimming switch that can be used once you remove the cover under the steering column, but I’m not clear enough on which wire that is exactly.

 

Does anyone happen to know about this? I'm not sure which wire would be considered "headlamp" (that's the gauge manufacturer's term) - it could be that it's a wire for the dashboard lighting, but I wouldn't know which wire to cut and I'm bound to cut the wrong one... I'm hoping someone else who has installed the Glowshift oil pressure gauge or some other gauge that should be connected to the "headlamp" circuit so that it dims when the dash is illuminated (when the headlights are on) knows which wire would be used here.

 

To answer your question, use dash lighting.

I'm on my work computer without my D2 Rave/wiring manual however (avoiding work though) -- for illumination, you should be tapping into a wire that goes to any of the other dash lamps.

So - for example, splice off the radio illumination wire, or the wire that goes to illumination in the climate control unit, or something. Or the illumination wire off any one of the switches in the switch panel (rear defrost, air suspension, hazards, front heated windshield, etc) *you'll have to find on the wiring diagrams or search around on here but make sure you are using the illumination wire. Maybe cigarette lighter lamp too altho I can't recall if that one dims... I'm sure it's tied into the same circuit tho for simplicity's sake.

Pretty sure last time I did this on a D2 I used whatever the wire was on the radio harness for illumination.