AIRmatic, Function [GF32.22-P-0003A]

Model 220 except CODE (487a) Active Body Control (ABC)







The AIRmatic The system is a fully supporting air suspension system. The system provides both static and dynamic support by means of four air bellows located at the wheels.

The AIRmatic system also features the following additional functions:

- The level control The allows both manual and speed-responsive, automatic raising/lowering of the vehicle level.

- The electronic level control system The 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.

- The "Adaptive Damping Sysytem" (ADS) changes the damping forces according to the road conditions and driving style of the driver. The road conditions are determined by vertical acceleration pickups at the body of the vehicle. The driving style (horizontal acceleration) is calculated using the vehicle speed and turn angle.

- Phased in as of 09/00, the damping is set to the sporty damping level at vehicle speeds >160 km/h.

Advantages
- Higher level of driving safety and ride comfort due to:
- Adapting damping to road conditions and driving style.
- Low location of center of gravity.
- Low aerodynamic drag and therefore low fuel consumption.
- Less lift at front axle.

- Individual adaptation due to:
- Raising vehicle level for poor road surfaces or driveways.
- (Up to 08/99 )
- 2 possible damping levels for comfortable or sporty driving style.
- (As of 09/99 )
- 3 possible damping levels for comfortable, sporty or extremely sporty driving style.

- Driver information:
- Higher vehicle level and sporty damping level displayed by means of indicator lamps in switches.
- Warning appears on multifunction display in instrument cluster if vehicle level is too low.




Function overview
The functions of the pneumatic closed loops are controlled using the components of the electric/electronic system.

The AIRmatic control module receives input signals from the following components:

- ESP control module (via CAN)
- Engine control module (via CAN)
- Transmission control module (via CAN)
- Instrument cluster (via CAN)
- Steering angle sensor (via CAN)
- ADS comfort and sport switch (via CAN)
- Level adjustment switch (via CAN)
- 3 body acceleration sensors
- 2 front axle level sensors
- 1 rear axle level sensor
- 1 AIRmatic pressure sensor
- Voltage supply and ground

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

- 4 level control valves
- 1 main reservoir charge valve
- 4 ADS damper valves (each with 2 solenoid valves)
- Multifunction display in instrument cluster Indicator lamps in switches: ADS comfort and sport, level adjustment
- Air compressor

The AIRmatic control module uses the input signals to decide which of the 3 functions must be controlled:

- Level adjustment
- Level control
- ADS

Several control functions can be processed at the same time.