I have a Pioneer DEH-P800PRS receiver and am trying to get the dimmer feature to work. It is turned on in the setup menu. The manual says the HU should dimm when the car lights are turned on. No other information is given.

Does the orange wire coming from the back of the receiver get attached to the orange wire on the Honda harness?

 

Did you connect the ILLUMINATION wire in the back of the headunit?

 

I had the ILL wire going to orange/white on the harness. Switched to flat orange and it works.