I am installing a boost gauge in my 04 Silverado and was wondering what is the best lead to tap into for the illumination? Its a Ultra Lite 2 by Autometer so it has LED's instead of regular bulbs. I tapped into the radio dimmer wire and the gauge just flickers, it doesn't dim with the rest of the dash. Im not sure what else to use since my headlights are automatic and would rather not just use the ignition switch cuz I only want it lit when the lights are on.

 

Doubt it's the best spot, but I tapped off from the passenger seat belt light. I think there was three wires going into it. I used a volt meter and turned the dimmer up in and down and found my two from the connector. Guage is bright and seat belt still works fine.

 

Tap into the actual dimmer switch itself. Use a voltmeter and see which wire will dim and brighten the buld as your moving the dimmer switch. This type splicer with a spade is what I used. Good luck

 

LEDs wont dim like regular incandescent bulbs, they tend to dim very slightly then just shut off.

 

I didn't think of the fact that LED's don't really dim when I was looking at gauges. Thankfully at night the face doesn't light up just the numbers do which keeps it from being super bright. However, from driving it the last few days I have noticed that there are certain points where my lights come on but its not really that dark (light rain, fog, etc..) so the gauge lights up and the numbers light up white and basically match the color of the face and you cant read it. So for now I hooked up a small toggle switch under the dash to flip the gauge illumination off (so numbers go back to black) for these rare occasions. Im going to experiment with the dimmer switch as suggested above but I don't think the problem visibility right at dusk or in fog is going to go away, might have to keep the switch or switch to a different gauge.