Whistle Noise at Highway Speeds with HVAC System in Recirculation Mode

Customers may comment of a whistle noise from instrument panel (I/P) area while driving at highway speeds with HVAC system in recirculation mode. The noise may also be present at lower vehicle speeds, with high cross winds.

The noise may be caused by a gap between the rubber seal on the recirculation door and the sealing surface in the blower upper case assembly. This gap may cause a whistle noise when the HVAC system is in the recirculation mode and blower motor is On.

Follow the procedure in this bulletin to verify and repair the noise condition.

1. Verify whistle noise is coming from the recirculation door area in the I/P by performing the following steps:

1.1.	Remove the I/P upper trim panel and insulator. (Refer to "Instrument Panel - Upper Trim Panel" removal procedure in the Vehicle Interior Systems section of the appropriate model year Body/Repair service manual.)

1.2.	Drive the vehicle at highway speeds with HVAC system recirculation mode On and blower switch on the LOW setting.





1.3.	Apply pressure against the recirculation door toward the front of the vehicle and see if the whistle noise goes away.

•	If noise goes away, continue to next step.

•	If noise does not go away, refer to "Windnoise Diagnosis and Repair" in the General Information section of the appropriate model year Body/Repair service manual.

2. Disable the passenger air bag. (Refer to the "Disabling the SIR System" in the appropriate model year SIR service manual.)




Notice:  Be careful not to allow recirculation door stop to fall into the blower motor assembly.

Important: The following steps are a blind operation. The recirculation door stop can be found under forward edge of recirculation door seal and is triangular in shape.

3. Locate the recirculation door stop at the top front, outboard edge of the blower upper case assembly.
4. Apply pressure with finger(s) to snap off the recirculation door stop from blower upper case assembly.
5. Reach into the opening of the blower upper case assembly and retrieve the recirculation door stop that was removed.
6. Enable the passenger air bag. (Refer to "Enabling the SIR System" in the appropriate model year SIR service manual.)
7. Drive the vehicle and verify the condition has been repaired.
8. Install the I/P upper trim panel and insulator. (Refer to "Instrument Panel-Upper Trim Panel" installation procedure in the Vehicle Interior Systems section of the appropriate model year Body/Repair service manual.)

To receive credit for this repair during the warranty coverage period, submit a claim through the Saturn Dealer System as follows: