Thanks for the responses so far. The one thing I find interesting is that (based upon your responses) it seems the dimmer circuit (or the switch) has been shorted or improperly tapped. But for my installation the head unit was wired with a harness, and no wires were cut or spliced. From what I saw of the harness, it appeared to simply plug in the back of the unit and into the existing wiring. Is there any way to cause a problem with the circuit if only the factory radio was unplugged, and the new harness and head unit were simply connected?

BTW, the technician had already placed a call to Honda to check on a dimmer switch, and he was informed that it is integrated in the instrument cluster and cannot be purchased separately. The tech subsequently placed the order for the cluster ($320), and it should be in by Tuesday.

I am still holding out for a better diagnosis of what happened, as the shop's owner will be in this week. FWIW, it is a VERY reputable shop in town here, and the owner has a myriad of experience. Unfortunately, when my receiver was installed, he was in Vegas for the CES, so he has yet to look at my car. At this point in time, I am expecting nothing less than a satisfactory resolution. I was just looking for some insight, because this occuring just bugged the heck out of me.

Thanks and regards,

David Liske