Hey guys, Looking for some clarification regarding installing a prosport electrical boost gauge in my girlfriends S5 Turbo II. The gauge itself is hooked up. However it simply is white faced with the key turned to Acc/on. I'm trying to wire it into the headlight switch so it changes colors when the headlights are turned on. Does anyone know which wire to tap into on the headlight switch?

 

Instructions will have been provided with the gauge telling you how to make that work. If you lost yours, simply go to their website. All of the instructions for their entire lineup are available. I lost the original instructions to my wideband and had to print them from their site.

Edit for comprehension fail...

An easy way to do this is to tap into one of the center console wires or the headlight switch harness itself. Take a multimeter set to 20dc volts and back probe wires until you find one that only sees voltage when the switch is on. Personally, I use the illumination for the suspension controls in the center console.

 

The RX7 maula has wiring maps and pin out and color coded wire labels that will help you find the right wire.

I found mine for my boost gauge but it was over 10 years ago that I did it.