Hello,

Need to catch a wire somewhere in the car that that will dim my NAV when the headlights go on. I know this topic is heavily discussed but I do not see a definitive answer where I can splice into a particular colored wire, preferably in the car. I am not great at testing the wires and there are a lot to choose from.

This is a 2004 Tahoe with XM and Bose. Crutchfield mentioned going to the headlight thru the firewall. I would prefer not to do this but I will. If I do this does anyone know if I connect to the yellow or black wire at the headlight bulb?

I have the unit installed and left this wire under the dash and accessible. This is wired with a GMOS-04 and an Axxess steering wheel module. A wire under the center console cup holder would be ideal. Any suggestions appreciated.

Thanks

Bob

Just wanted to mention that I tried both the orange and orange/white wires on the GMOS-04. This did not work as I expected from reading post and talking to Crutchfield. Thanks

I tapped into yellow wire at the headlight bulb connection. I fed the wire through the firewall and connected it to the orange/white wire in the back of the pioneer x930bt. This works great and the NAV only goes into night mode when the headlights come on and not when the running lights are on. The brown/white wire and purple/white behind the headlight switch did not work for me since both those wire are live when the running lights are on. This meant that my NAV was in night mode all the time.

Well I have the headlight switch out I also took out the instrument cluster and tested all those harnesses without any good results. The feed through the firewall comes right out at the parking brake and I should have saved some time and just done this right away.

Hopefully this will help someone else.

One small complication. When you turn on the high beams in the Tahoe the low beam bulb goes out and the NAV goes to daytime mode and blinded my wife:-)

Simple solution get 2 diodes at Radio Shack for $1 and do the 4 hi mod or 6 high mod. I actually wanted to do this anyhow. I guess the other option would be tap the 12v feed on the high and low beam but I did not want the signal fluctuating as you move back and forth between the hi and lo beams this i thought not be good for the unit.