Subaru XT 1988 Service Manual page 766

SUSPENSION
Pressure switch
If the pressure in the air tank rises, the pressure sensitive disc
pushes the guide pin up to open the moving contact, and the
switch is opened.
closed.
Pressure sensitive disc
Fig. 12
When the pressure drops. the switch is
r-Moving contact
/
Guide pin
L4-1292
9
4-1