Engine "On"
Ride level compensation, raising and lowering the vehicle's ride height as well as filling the accumulator are permitted when the engine is running. The compressor also starts up during every control operation.
Ride level is still compensated outside the narrow tolerance range of +/-10 mm.
As long as the vehicle is stationary, high speed filtered ride level signals are used to detect a change of load. This allows the system to react immediately to changes in ride level.
As soon as the vehicle is travelling, it changes over to low speed filtered ride-level signals. The system no longer reacts to bump movements caused by road surface unevenness. A mean value is formed over a prolonged period of time, i.e. payload is only altered by the progressive emptying of the fuel tank.
The high speed filter is not used until the vehicle is stationary again and a lid is opened. If no lid is opened, the vehicle logically cannot be loaded or unloaded.