Airwell VVFA Series Service Manual page 51

[30] High pressure switch failure
If connection between pressure
switch and connecting board is
If the system pressure meets the
condition that pressure switch
Make pressure switch terminal
circuit, check if failure exists still
good
Yes
shuts off
Yes
Make pressure switch
close, measure if terminal
is conductive by multimeter
Yes
If the system is clogged
No
on connecting board in short
No
Replace pressure switch
and measure again
No
No
Replace pressure switch
No
Yes
Check the piping system
Yes
Replace connecting board
49
Re-connect