I have a Z2 installed in a Solstice, and I used the Metra GMOS-LAN-04 to connect to the GM wiring harness. I hooked up the GMOS-LAN-04 Illumination wire output (orange) to the Z2 Illumination input. Everything works when the low beams on the car turn on - the Z2 display dims with the audio page and the nav screens go to nightime mode.

But when I switch to the high beams, the display goes back to full brightness, blinding me at night in this tiny car. Has anyone else seen this problem? I suspect a problem with the GMOS-LAN-04 programming and have called Metra. They said that I was the first to see this problem.

Surely someone else using the GMOS-LAN-04 or GMOS-LAN-03 has this problem. I may have to hack into the car headlight wires. I don't suspect a Z2 problem, as I expect the illumination input lead is simply looking for +12 volts with the headlights.

Anyone out there have any idea why this would happen?

Many thanks.

sounds like a communication error/programming error with the GMOS, but either way, you can simply hook up the ill wire from the AVIC to the parking light wire in the car, not the one on the radio harness. The parking light wire is brown, in the driver's kick or @ BCM(BCM is part of the fuse box below the glove box), Connector 3, pin A7. Either one will work, just go to the one that is easier to get at. As always, test the wire before connecting to it. HTH

Does that wire go to +12V when the parking lights turn on, then to zero when they go off? I assume that is what the Z2 wants to see to sense nighttime. Keep in mind that the new GM cars (including my Solstice) have automatic headlights.

Thanks for the help. I am not anxious to tear apart the dash again, but I can't live with it the way it is now.

i would try tapping-in to the 12V+ that feeds the dash lights (If you can't find, or don't have, an illumination lead)... If your dash lights only work with the beams on.... my 2c.

don't hook it up to a lead that feeds the dash lights, they are dimmer wires, not illumination wires, the voltage fluctuates with the dimmer switch on those wires. If you connect to the parking light wire that I stated, it will work. That wire reads 0 when the parking lights are off, and 12+ when they are on. When your headlights are on (high or low) the parking lights are also on, so your avic will not get brighter when you don't want it. It should also work with auto lights, but just test the wire to see if it automatically goes to 12+ when your auto lights turn on, if so, you are all set.

true, dash is on dimmer.... go for constant 12 when ligths are on....