My 2009 MC has Nav and bluetooth if this is related to the question that follows:

On the dashboard, by the defroster vents, near the windshield, and exactly center about three inches from the windshield is a circular thing that sort of looks like a button that could be depressed. But it's not a button. I just wonder what's the purpose of that circular thigamagigy. It looks similiar to the button for the hazard flashers but it's smaller, and isn't really a button.

Anyone know? Thanks, Finner

 

I know what you're talking about, but I have no idea what it's for! Hopefully someone can tell us.

 

Its for the auto headlights. If you don't have that option its just a blank. If you do have that option it senses the amount of ambient light for the computer to know to turn on/off the headlights.

 

Thanks Jeremy!

 

No, the auto headlight (and also auto wiper) sensors are up on the windshield by the rear view mirror. The sensor on the dash is part of the auto climate temperature control.

 

Alrighty, thats a change from 1st to 2nd gen.

 

I just confirmed from wiring diagrams. The configuration is the same for 1st and 2nd gen. The small box on the windshield by the rear view mirror holds sensors for auto headlights and auto wipers. The button-like thing on the dash is a solar sensor which is part of the automatic cabin temperature control.