Starting 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.

When front blower motor is activated, A/C auto amp. gradually increases duty ratio of front blower motor control signal to prevent a sudden increase in discharge air flow.
It takes approximately 8 seconds for air flow to reach HI from LOW.

Fig 1: Starting Air Flow Control Graph
Courtesy of NISSAN MOTOR CO., U.S.A.