Does anyone know? Above your head inside the H2 Drivers seat in the roof.

There are two sensors above your head. One towards the front and one behind towards behind your head.

Which one is which and what do they do? I have one making a racket and I want to replace it. Nobody knows which one is which.

 

I assumed 1 was a temperature sensor for the climate control and the other was the on star microphone... Never checked though so I could be wrong

 

Onstar mic and Onstar speaker probably the speaker making some type of noise maybe grounding

 

I thought the onstar speaker was going through the radio?

 

Well to troubleshoot if I held my finger on it as I went down the road and the noise stopped. When I release my finger it goes to town on making a racket.
To stop it until I could figure out what it was, I just shot white lithium grease in it and it did stop it for a week. I didnt care if it messed it up. I knew whatever it was I would be getting it fixed soon! I am just trying to figure out what exactly it is and how to change the darn thing.

 

I say one is speaker only because I popped the cover off before and it looks like a little speaker.. I have a aftermarket nav radio so I don't use onstar so guess I don't know forsure

 

I remember reading on here a couple of years ago that one is the Onstar microphone and the other is the climate sensor. AND the climate sensor has the tendency to make a noise. I don't remember what the fix was. Sorry. Try searching though.

 

The one towards the front is the onstar mic and the one above your head is for the climate control. Inside the climate control sensor is a small fan, that fan is known for getting clogged with dust/dirt which will cause a rough spot and will eventually make noise.

 

im going to try cleaning both with compressed air and see if that helps. If not I am going to get the dealer to install a new one. They are not expensive at all

 

I just went through all of this. that little fan is what makes the noice. $47.84 and 15 minutes to pull the headliner down to replace will fix that issue. That does have a fan/ sensor in there for the climate control. I pulled that out and it looked like someone filled it up with dirt.