I am getting feedback through my OnStar speaker (the little speaker that mounts in the headliner just above your left ear) when my truck is cold. When the truck warms up no problems at all. It's just enough humming to drive a person nutz ! Any ideas? I do have a warranty but I would rather do some trouble shooting first.

I was wondering what the heck it was. Thought it is a speaker, but never noticed any sound; never called OnStar though. I’ll check the service manual and let you know if I find something.

Let’s keep the forum alive…

This message has been edited. Last edited by: Ken,

Hmm, thought that was climate control sensor, and onstar played through the stereo speakers, just lik e the door chimes do.

srode- Good Call . I did some looking into the "speaker" and found out that it is for the Climate Control. Still no one has any ideas what to do/ how to fix?

I believe there's a little fan in there, it's probably worn out and needs replaced, think you need to replace the assembly.

Srode is right, it is air temperature sensor assembly, and there is a little fan in it. No fix, just replacement procedures in the manual. Since you still have warranty, have it replaced.

Thanks Guys!

They named the part as an Aspirator. $110.00 w/tax and it's fixed.