Flap Control – High Line System

AIR CONDITIONING

DESCRIPTION AND OPERATION

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Flap Control – High Line System
The position of the ram air flaps is automatically controlled by the ATC ECU. The positions of the recirculation flaps 
and the distribution flaps are either automatically controlled by the ATC ECU or manually controlled by the related 
switches.

Ram Air Flaps
The ATC ECU progressively closes the ram air flaps, in four steps, as vehicle speed increases, and opens them again 
as vehicle speed decreases. At the maximum closed position, 90% of the fresh air inlet area is closed off. A hysteresis 
of 9 mph (15 km/h) prevents the ram air flaps from hunting at a constant vehicle speed.

Ram Air Flap Positions

A = Flap position, % open; B = Opening speeds, mph (km/h); C = Closing speeds, mph (km/h)

M82 0816

0

20

40

60

80

100

28

(45)

47

(75)

63

(100)

91

(145)

38

(60)

100

(160)

56

(90)

72

(115)

A

B

C