HVAC Mode Door Flutter Noise (Install New Mode Door Actuator Levers)

Some customers may comment on a Heating, Ventilation and Air Conditioning (HVAC) mode door flutter noise. This condition usually occurs when the mode knob on the HVAC control head is set one detent counterclockwise from floor mode.

This condition may be caused by a loose fit between the levers that drive the mode door and the door.

Important: Re-calibrating the HVAC control head actuators may eliminate the noise temporarily but it is not to be used as a long term repair. The noise may come back.

Technicians are to replace the mode valve cam actuator levers using the following procedure:

1. Remove the left insulator panel. Refer to the illustration above and the Instrument Panel Insulator Panel Replacement-Left Side procedure in SI.



2. Remove the knee bolster. Refer to the illustration above and the Knee Bolster Replacement procedure in SI.



3. Remove the communication interface module from the support bracket and position it aside. Refer to the illustration above and the Communication Interface Module Replacement procedure in SI.



4. Remove the mode actuator. Refer to the illustration above and the Mode Actuator Replacement procedure in SI.



5. Remove the mode cam bracket (1), mode cam (2) and the mode cam levers (3 and 4). Refer to the illustration above and the Mode Cam Replacement procedure in SI.
6. Install the new mode cam levers (3 and 4), mode cam (2) and the mode cam bracket (1).
7. Install the mode cam actuator.
8. Install the communication interface module into the support bracket.
9. Install the knee bolster.
10. Install the left insulator panel.

Important: Any time a mode actuator or the HVAC control module is replaced, the HVAC control module must be calibrated to ensure proper air distribution.

11. Calibrate the mode actuator by simultaneously pushing the A/C and RECIRC buttons on the HVAC control module 3 times each, within 2 seconds of the initial push.

•	The A/C and RECIRC button LEDs will flash while this calibration is taking place.

•	The calibration will take anywhere between 10-30 seconds depending on battery voltage.

•	The LEDs will quit flashing when the calibration is complete.

12. Cycle the ignition and verify proper operation of the HVAC system.

For vehicles repaired under warranty, use: