I am a newbie to this Z2 that I just had installed in my 2004 Chevy 2500HD pick up truck. My problem is this, I want it hooked up so it dims when the headlights go on. The installer said it can not be done because the headlights go on and off automatically. If someone con tell me how to do it I will pass it on to him and he will try it.

Thanks

Just run the illumination wire to the illumination wire on the headlight switch/dimmer.

Is the guy who installed it a pro? Auto-headlamps still have to send a signal to the headlamps, so there is always a way to tell the unit to dim

EDIT: Just noticed that this is for the Z2, but I cannot imagine it's any different than the D3, dimming-wise.

Also, did you have to buy a particular module to keep the door chimes and/or Onstar? If so, chances are good that module would do this for you. I have an '06 Impala that needed the GMOS-LAN-01 kit to do this, and the illum. wire was right there.

One problem with those trucks. I have seem several times when it is connected to the dimmer that it sometimes won't work. What you need to do is run a wire from the dash to the parking light bulb. The wire colors are orange/white on the Z2 to the Brown wire at the parking light. This will help.

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Thank You Guys Very Much

At the switch it's negative trigger that does headlamps and parking lamps both, and the factory radio is controlled by data.

I would reccomend a gmos-01 for non bose, gmos-04 with bose. Get the right part, and you will not lose any warning chimes, provide a "healthy" state to the BCM as far as the radio is concerned, and the module will give you a vss and dimmer wire.

Yeah, the GMOS-01 did all the work for me. However, IDK if the VSS is reading right...the "0" never changes (although the Speed Pulse count was at 236 last time I checked)

Along with the VSS and illumination wires, the GMOS also finds the backup wire, too, which saves some time during the install.