GF32.22-P-0003GZA AIRmatic, Function

GF32.22-P-0003GZA AIRmatic, function
- with CODE (489) AIRmatic (air suspension with level adjustment without ADS adaptive damping system)
- with CODE (494) USA version

Component Identification:

Basic function
When the air compressor delivers air to a bellows, the vehicle level increases at the wheel concerned. Conversely, the vehicle level decreases if air escapes into the atmosphere through the pressure release valve of the AIRmatic compressor unit (A9/1). The system is equipped with a central reservoir as a compressed-air reservoir. This increases the adjustment speed when raising the vehicle and permits regulation in the sleep and run-on mode.

The complete function of AIRmatic can be subdivide d into 2 subfunctions:
^ Level control enables a manual, as well as a speed dependent automatic raising or lowering of the vehicle level.
^ The electronic level control system controls the vehicle level at the front and rear axles and ensures the vehicle level remains constant according to the driving and vehicle loading conditions.

Advantages of AIRmatic
Greater driving safety and ride comfort due to:
^ speed-dependent level control;
^ lowering of vehicle level with sporty driving style and at high speed so that no compromises in vehicle dynamics have to be made;
^ adaptation of suspension to road surface condition and driving style;
^ reaching a lower center of gravity position;
^ reaching a lower aerodynamic drag and thus a lower fuel consumption;
^ less lift at front axle;
^ an individual adaptation by increasing the vehicle level for poor roads or when off road;
^ indication of the raised and lowered vehicle level stages by a function indicator lamp in the level adjustment switch (N72/1s2), and a warning given on the multifunction display (A1p13) in the instrument cluster (A1) if the vehicle level is too high.

Function overview
The functions of the pneumatic control loop of the AIRmatic are controlled with the components of the electrical system and electronic system.

The AIRmatic control unit receives input signals from the following components via the CAN data bus:
^ ME-SFI [ME] control unit (N3/10)
^ Fully integrated transmission control (VGS) control unit (Y3/8n4) (target and actual gear)
^ Central gateway control unit (N93)
^ Instrument cluster (outside temperature and circuit 61 "engine running")
^ Level adjustment switch
^ Steering angle sensor (N49)

The AIRmatic control unit receives input signals from the following components via discrete inputs:
^ Left front level sensor (B22/8)
^ Right front level sensor (B22/9)
^ Left rear level sensor (B22/7)
^ Right rear level sensor (B22/10)
^ AIRmatic pressure sensor (Y36b1)

The AIRmatic control unit controls the following control functions on the basis of the input signals:
^ Level control
^ Level adjustment

Several control functions can be processed at the same time.

In the AIRmatic control unit, the input signals are converted into output signals for the following components:

Actuators of level control and level adjustment
^ Air compressor motor (A9/1m1) via AIRmatic relay (K67)
^ AIRmatic pressure reduction valve (A9/1y1)
^ AIRmatic valve unit (Y36)

For driver information
^ Multifunction display in instrument cluster
^ Indicator lamp in level adjustment switch