Automatic Air Flow Control

WARNING: This page is about a different car, the 2011 Infiniti QX56. However, it is still accessible from the selected car via links, so may be relevant.

A/C auto amp. decides target air flow depending on target front air mix door opening angle.
A/C auto amp. changes duty ratio of front blower motor control signal and controls the air flow continuously so that air flow matches to target air flow.
When air outlet is VENT or B/L, the minimum air flow is changed depending on sunload.

Fig 1: Air Flow Chart
Courtesy of NISSAN MOTOR CO., U.S.A.