Level control valve unit function - GF32.31-P-4500-03B
For reasons of safety only one valve is ever actuated at the same time. If an axle is too low, cycling takes place between the left and right level valve.
Raising the vehicle
The front left, front right, rear left and rear right level valves (y1, y2, y3, y4) are opened as required and the compressed-air stored in the central reservoir or generated by the air compressor motor flows from the level control valve unit (Y36/6) to the individual spring struts. As soon as the required vehicle level is reached at a front wheel, the respective level valve (y1 or y2) closes, the other valve still remains open until the same vehicle level has also been adjusted at the other wheel. At the rear axle both level control valves (y3 and y4) close when the vehicle level averaged between the right and left wheel corresponds to the specified level set by the control module.
Lowering the vehicle
All the wheel level control valves (y1, y2, y3 and y4) are open in the level control valve unit (Y36/6).In addition the AIRmatic pressure release valve (y1) in the AIRmatic compressor unit (A9/1) is open and the compressed-air is reduced via this valve. At the same time the level valves of the individual wheels remain open until the desired vehicle level is reached at each front wheel and at the rear axle.