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ECAS – Electronically Controlled Air Suspension
ECAS components
Control electronics (ECU) The control electronics is the core of the system, to which the individual components are connected with plug-in connections. Solenoid valves Combining specially developed solenoid valves into compact block valves are of overall installed size and the effort required for connecting is greatly reduced. The solenoid valves, controlled as actuators by the electronics, convert the applied voltage to a pressurizing or depressurizing process (such as raising, lowering or stopping the air ow in the bellows).
ECAS solenoid valve
ECAS distance sensor
Distance sensor A rotary movement of the lever registers every change in the distance between the assembly and the axle (comparable with a standard air suspension valve). The value of the change in inductivity is measured in short intervals and is converted into a distance signal by the electronics. Pressure sensor The pressure sensor is only required for systems with tire impression compensation (load-dependent travel height change resulting from tire impression).
ECAS pressure sensor
Service and maintenance information
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The ECAS system is maintenance-free. A diagnosis in the ECU program allows the system to inspect itself. Another check of the system is not required, besides checking the system parts, which cannot test themselves (distance sensor rod, linkage, warning lamps, etc.). If an ECU error is detected, it is indicated to the driver via the display. Only then does the system have to be tested in a workshop.