LR3/Disco 3
The valve block has four air pipe connections which use 'Voss' type air fittings. The connections provide for air supply
from the air supply unit, air supply to and from the reservoir and air supply to and from the front and rear valve blocks. The
connections from the air supply unit and the front and rear control valves are all connected via a common gallery within
the valve and therefore are all subject to the same air pressures.
The valve block contains a solenoid operated valve which is controlled by the air suspension control module. The
solenoid valve controls the pressure supply to and from the reservoir. The solenoid has a resistance value of 2 Ohms at a
temperature of 20°C (68°F). When energised, the valve spool moves allowing air to pass to or from the reservoir.
The valve block also contains a pressure sensor which can be used to measure the system air pressure in the air springs
and the reservoir. The pressure sensor is connected via a harness connector to the air suspension control module. The
control module provides a 5V reference voltage to the pressure sensor and monitors the return signal voltage from the
sensor.
Using this sensor, the control module controls the air supply unit operation and therefore limits the nominal system
operating pressure to 244 lbf/in
2
(16.8 bar gage).
AIR SUPPLY UNIT
