Abstract: To detect a defect or failure of a compressed air load circuit in a compressed air system for vehicles, pressure is measured in compressed air load circuits and evaluated in an electronic control unit, which briefly shuts off the compressed air load circuits, measures pressure values and/or determines pressure gradients during the shutoff time and compares the pressure values and/or the determined pressure gradients with a respective threshold value, identifies defective circuits and definitively shuts off circuits detected as defective if the results are below the threshold value.

Abstract: An electronic compressed-air system includes a compressed-air supply part having a compressor and a consumer part having load circuits. The load circuits are supplied with compressed-air via solenoid valves. At least one load circuit is provided with a pressure reservoir. The pressure in the load circuits is monitored by pressure sensors, whose signals are evaluated by an ECU that controls the solenoid valves. The load circuits include service-brake circuits having a compressed-air reservoir, secondary load circuits and a high-pressure circuit, wherein the solenoid valves of the service-brake circuits and the solenoid valves of the secondary load circuits are open in a de-energized normal state and the solenoid valve of the high-pressure circuit is closed in the de-energized normal state.

Abstract: An electronic compressed air system for vehicles includes a compressed air supply part having a compressor, a compressed air consumer part having load circuits forming an air-suspension circuit, and service-brake circuits having reservoirs. The load circuits are supplied with compressed air via solenoid valves. The pressure in the load circuits is monitored by pressure sensors whose signals are evaluated by an ECU that controls the solenoid valves. The solenoid valve of the air-suspension circuit does not include reservoirs and is closed in the de-energized normal state. The solenoid valves of other load circuits, especially of the service-brake circuits are open in the de-energized normal state. With a pressure demand of the air-suspension circuit, the associated solenoid valve is switched by the ECU to open position to establish communication with the compressed air supply part and/or with the service-brake circuits or with the reservoirs thereof, to refill the air-suspension circuit.

Abstract: A device housing, especially for accommodating an electronic unit or a mechatronic unit, has parts which are sealed against one another in assembled condition via an encircling, stationary seal. At least one pressure-relief device is integrated into the seal for admission of air into the housing. The seal is formed at least in part as a lip that opens under overpressure conditions inside the housing. To allow any water that has penetrated to flow away, the housing is mounted vertically, with the pressure-relief device disposed at the bottom.