I had mine installed at CarToys. They initailly didn't hook up the illumination wire at all. I took it back and they wanted to charge me $50 to hook it up. They said it was because of the way GM did the light control through the brain. After an hour of arguing they said they would hook it up. It now works with the headlight switch turned on but not when the automatic headlights come on.
I can hear the relay clicking when the headlight switch is turned on. So I'm going to listen to the clicking and find the relay... and then hopefully find the right wire to connect it properly.
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