Air Intake

IHKR1 AIR INTAKE

The IHKR system can draw fresh air in from outside the vehicle, recirculate air already inside the vehicle, or both. Fresh air and recirculating air flaps open and close the fresh and recirculating air inlets.

FRESH AIR FLAPS







The left and right fresh air flaps are operated as a pair by the fresh air flaps stepper motor. The position is controlled by the control module.

At vehicle speeds up to 36 mph, fresh air flap position depends on blower knob position:
- With the blower knob at "0", the fresh air flaps are closed
- As the blower knob enters the "wedge", the fresh air flaps are 40% open
- As the blower knob is turned through the "wedge", the flaps open progressively
- When the blower knob reaches the end of the "wedge", the flaps are 100% open The flaps remain 100% open with the blower knob at position "1" or higher

At vehicle speeds above 37 mph, the control module partially closes the fresh air flaps, to counteract the ram-air effect. By 87 mph, the fresh air flaps are only 40% open, even if the blower knob is at the end of the "wedge" or higher.







Prior to engine start-up, the fresh air flaps are fully open. When the ignition switch is turned to "Run" the control module moves the flaps to the correct position. At engine shutdown, the fresh air flaps again move to the fully open position.

RECIRCULATING AIR FLAPS
The control module also positions the recirculating air flaps, using the recirculating air flaps stepper motor.

During normal A/C system operation, the recirculating air flaps are closed and only fresh air is drawn into the system. When the recirculating air button is pushed, the control module closes the fresh air flaps and opens the recirculating air flaps.

If, during A/C operation, the control module determines that maximum cooling is needed, it closes the fresh air flaps to 30% open and fully opens the recirculating air flaps.

Prior to engine startup, the recirculating air flaps are always fully closed. If the flaps are open at engine shut down, the control module closes them and fully opens the fresh air flaps.