boost gauge light wire, which dimmer

[nd240sx3]

ok what color wire is the one on dimmer that i want to plice boost gauge power wire into so i can dim and shit thanx

[mjjstang]

I used the red w yellow or was it yellow w red, and i traced the schematic to the dimmer for radi0 and everything, it all looked good, till I put a multimiter on it, and noticed that the brigher the ligts got the less voltage, so I guess I messed up but heres a bump cause I wanna know too. also I realized that if I went any dimmer than the highest, I couldnt even see em. even with the color condoms off. but thats on the crap autometer ones, plus i dont like much light in my car anyways so its perfect for me.

[nd240sx3]

i wanna know which wire on interior light dimmer is the one thanx hope someone can help

[mjjstang]

do the interior lights dim, wow even on my new car they dont but i donno.

[projectRDM]

Aftermarket gauges don't have a dim feature, unless they have a separate ground lead for the bulb (Autometer). If so, red/blue is illumination, red/yellow is dimmer. Most HKS/Greddy/Blitz/etc. gauges do not have a dimmer feature, JDM cars don't have dimmers at all.

The OE dimmer circuit varies the ground feed to the bulb, not +12V.

[mjjstang]

ok, but the autometer has a lead for dimmer, and the red yellow goes up in voltage as the lights dim, so that cant be used.

[projectRDM]

ok, but the autometer has a lead for dimmer, and the red yellow goes up in voltage as the lights dim, so that cant be used.

You don't seem to grasp the idea of how a bulb works. You're testing for voltage, try reversing it and check for ground, you'll see the opposite.

The red/yellow is a ground when the lights are on at full brightness, as the lights dim it will begin to show voltage because it's no longer a ground, since it's backfeeding through the bulb. On the gauge, at full bright, the red/yellow wire will provide a ground to one side of the bulb and illuminate it. As the ground is lost, the bulb will dim. All the OE dash lights do the exact same thing.

[mjjstang]

how bout this then, when connected to that red yellow wire, my gauge dims when panel brightens and gauge brightens when panel dims. but It really doesnt matter cause I am not planning on dimming it anymore anyways.

[projectRDM]

how bout this then, when connected to that red yellow wire, my gauge dims when panel brightens and gauge brightens when panel dims. but It really doesnt matter cause I am not planning on dimming it anymore anyways.

Christ mang, am I talking to a brick wall?

Autometer gauges have two wires for the bulb, black and white. White goes to red/blue, illumination +12v, black goes to red/yellow, illumination dimmer. Unless they reinvented the light bulb recently, there's no other way for it to work. How specifically is yours connected?