Patent ID: 7881840

Claim:
A level control system for a motor vehicle, by means of which a vehicle body is spring-suspended relative to at least one vehicle axle and which comprises the following components: a compressor ( 2 ) with an inlet ( 4 ) and an outlet ( 6 ), air springs ( 18 a - 18 d ), each of which is connected to the outlet ( 6 ) of the compressor ( 2 ) via a compressed air line ( 16 a - 16 d ), which may be shut off by a switchable directional control valve ( 20 a - 20 d ), at least one pressure sensor ( 10 ), which is, at least intermittently, connected to the outlet ( 6 ) of the compressor ( 2 ) via a sensor compressed air line ( 8 ), wherein the system checks as follows whether the compressor ( 2 ) functions properly: the pressure sensor ( 10 ) is connected to the outlet ( 6 ) of the compressor ( 2 ) via the sensor compressed air line ( 8 ), the compressed air lines ( 16 a - 16 d ), which connect the air springs ( 18 a - 18 d ) to the outlet ( 6 ) of the compressor ( 2 ), are shut off, the compressor ( 2 ) is switched on, the pressure increase at the pressure sensor ( 10 ) is measured, if the pressure increase per unit time exceeds a predetermined threshold value S, the system determines whether the compressor ( 2 ) functions properly, after checking whether the compressor ( 2 ) functions properly, the compressor ( 2 ) is switched off.