Silverado Onstar Headliner Speaker Rattle & Hum

**neversummer** · 07-02-2008, 03:38 PM

Hello everyone,

Has anyone had this problem or know of a solution, This is my 2nd silverado that has had this exact same problem, there is engine noise or hum coming from the speaker above the drivers head in the headliner. specially with the radio off you can hear it LOUD. does anyone know anything about this.

**dwill3015** · 07-02-2008, 09:31 PM

Is that a speaker? I was told it was a temp sensor for the auto-HVAC system. My onstar sound comes through my steareo speakers and the mic is on the upper console on the roof.

I too have hear sounds almost like feedback from time to time though.

**neversummer** · 07-03-2008, 02:57 PM

Yeah i dont know what it is. its getting engine noise and stuff at idle , i have the mic on the center console thing on the headliner also. but i dont knwo what this thing is but there are wires going to it when i pulled back the headliner a bit i could see into it. im gonna try and throw a piece of dynamat around it and see if that helps the rattle if i press on it the noise stops but its annoying as hell at idle with the radio off.

**Zupa636** · 04-13-2011, 11:23 PM

I had the same problem in my 2007 crew cab, so i took it apart today an found out that it is a small fan. I think it does have some thing to do with the HVAC controls.

**jfr1800** · 04-14-2011, 09:02 AM

Yes the little speaker is not a speaker at all it is a temperture senser that senses the cabin temperature for the auto HVAC system. If you unplug it the auto temerature comtrol will not work. The only way then to get the temperature to work is either full hot or full cold no in between. Suggest you go to the wreckers and get one to replace it. It can be replaced without taking down the head liner only pying it down slightly. The temperture senser plugs into the wiring harnes and the plastic speaker looking piece holds it in place.

JFR

**GM Customer Service** · 04-14-2011, 11:01 AM

I would also recommend replacing the fan if you are finding that this is a nuisance. You can get more replacement information from your local dealership. You can also get parts information by visiting http://www.gmpartsdirect.com/. If you have further questions, please feel free to contact me directly. Thank you.

Tricia, GM Customer Service.

**chounch187** · 06-27-2011, 10:23 PM

Hey guys, just found this thread via Google.

I recently purchased a 2007 Silverado (new body) LTZ 4x4 ext cab. A few days ago I heard a buzzing noise emanating from the corresponding "speaker-like" grille located in/near the headliner above-left of the driver. The noise only occurs at idle and is relatively loud. I did some internet research and also discovered the "grille" is actually a HVAC sensor/fan (is this true for 2007 models though?). However, after taking the vehicle into service this morning, the technician/advisor later said "everything was fine" and the computer was not showing any error codes.

I told him to check again and sitrep was 'the speaker is a BlueTooth speaker that's working fine'. I asked in confirmation if the "speaker-like grille" was a BlueTooth speaker or the temperature sensor/fan and the advisor told me it is actually a BlueTooth speaker (not the temperature sensor like everyone is saying).

What's going on here? Is he lying to me?

**GM Customer Service** · 06-28-2011, 01:11 PM

I would be happy to look into this further for you. In order to do more research, I will need the VIN for the vehicle. Thank you in advance.

Tricia, GM Customer Service.

**jfr1800** · 07-04-2011, 01:05 PM

The little speaker thing is definatly not Bluetooth, it is the cabin air temperature senser which allows the climate control system to work. There is a small fan in it which is causing the buz noise. It is the same in my 2006 as in the newer models as well. Changed one out in a 2005 for a friend of mine with one from a 2008 (wreck) and it worked just fine.

Hope you get some resolution to your problem.

JFR