I just had my z110bt installed, and the installer left the illumination wire dangling. I went back two days later and had him hook it up because the screen is so bright at night.
I have a 2005 avalanche (onstar and bose, I have the adapter to keep both), when he hooked up the illumination wire he hooked it up to the illumination wire coming out of the harness. however lights on or off screen stays the same, also when I go the connections screen with the lights on or off the illumination always says off.
Any suggestions on whats wrong?