Z2 IS INSTALLED AND EVERYTHING WORKS EXCEPT HEAD UNIT DOES NOT DIM WHEN HEADLIGHTS TURNED ON. ILL WIRE IS HOOKED PER INSTRUCTIONS. I HEARD OTHERS HAVE HAD THIS PROBLEM, I READ SOME ARE USING THE TRACTION CONTROL BUTTON AND TYING THE ILL WIRE INTO THE GRAY WIRE. ANY THOUGHTS? IS THERE A BETTER WAY TO DO THIS? THANKS!

Use a multimeter and check to make sure your actually tapped into a wire that goes to +12v when the lights are on.