Hey guys, new to the forum, and have been reading alot. Learned alot. I recently picked up an 04 Silverado 25000HD. Inside the cab above the driver's seat there is a tweeter speaker looking circular grill. When I start my truck, this noise like a small fan hitting someting starts also. It will continue until I shut the truck off.

What is this thing? Any ideas on what is going on?

Thanks
Chris

P.S. This sound is coming from the tweeter looking thing. If I place my hand over it the sound softens.

 

Removed wrong information.

 

If you have the automatic temp system it is the inside air temp sensor. There is a fan inside it, which is making noise. Parts dept call it a aspirator. If you replace it it comes out from between the headliner and roof. The grill holds it in place to the headliner.

 

Is this an easy part to replace? What is the process to replace this fan? Any ideas on the the cost of the part? Yes, I have the automatic climate control. Thanks for the help fellas, this has been driving me nuts ever since I got the truck.

Chris

 

INSIDE AIR TEMPERATURE SENSOR ASSEMBLY REPLACEMENT

REMOVAL PROCEDURE

1. Remove the left windshield garnish molding.
2. Remove the left center pillar assist handle.
3. Remove the left center pillar garnish molding.
4. Remove the left sunshade.
5. Gently pull down the headliner.
6. Disconnect the electrical connector from the inside air temperature sensor.
7. Partially remove the inside air temperature sensor from the headliner.
8. Remove the sensor grille from the inside air temperature sensor.
9. Remove the inside air temperature sensor from the headliner.

Not sure of the cost of the sensor.

 

Thank you acnas. I will look/call around for the part and go from there. Thanks again for your help. I really appreciate it.

Chris

 

I finally got around to putting that part in acnas. Was even easier than your intructions sounded. Again, I thank you for helping me out.

Cost of part from the local GM dealer: ~ $40
Cost of aftermarket part: ~ $25 - $35 (didn't want to wait for shipping)

Time: ~ 20 - 30 minutes

Piece of cake, and no more buzzing in my ear.

Chris

P.S. I included all the details for other people who may have this problem.

 

No problem.