Vacuum Element For Blend Flap

Purpose
The blend flap actuator motors control the blend flaps (air coming directly from evaporator to center nozzle) for control of the air flow to center nozzle or the left and right side separately.

Function
The blend flap actuator motors are controlled by the electronic center nozzle control module, A/C bus and electronic stepping motor control module depending on the desired air outlet temperature at the center nozzle.

Blend flap control via automatic A/C pushbutton control module

Defrost-function
Blend flap open 0% (only when center nozzle is in AUTO position)

REST-function
Dependent on exit temperature (only when center nozzle is in AUTO position)
Automatic A/C switched off
Blend flap open 0%

Blend flap control via exit temperatures
If the center nozzle is in the AUTO mode, the blend flaps are regulated depending on the exit temperatures and the set air quantity potentiometer for the center nozzle

Blend flap control via center nozzle
In the center nozzle manual mode the blend flaps are set by the left and right selection dials (potentiometer) for the center nozzle.
Left/right selection dial (potentiometer) 0-100 % corresponds to left/right blend flap position of 0-100 % (linear).