TM 9-2320-363-20-1
5.2 With the engine running and the air conditioner
and blower on, both terminals will show voltage
when the compressor should be engaged; one
terminal
will
show
voltage
when
the
compressor should be disengaged.
If there is no voltage, there is a problem in the
electrical system from the batteries to the
thermostatic switch. Check all circuits for the
cause, and repair or replace the wiring or parts.
In all other cases where the compressor is not
engaging
and
disengaging
properly,
the
thermostatic switch is the cause. Replace it
with a new switch.
6. Shut down the engine and, to prevent accidental
electric shock or shorting during dash assembling,
disconnect the batteries.
7. Assemble the dash.
LINE RESTRICTIONS
A restricted suction line causes low suction pressure at
the compressor and little or no cooling. A restriction in a
line between the compressor and the expansion valve
can cause high discharge and low suction pressure, and
insufficient cooling.
Usually, areas of ice or frost build-up mean a blockage.
Parts that often freeze up are probably corroded or
inoperative and should be replaced. Parts (such as the
expansion valve) that freeze up once in a while may do
so because of moisture in the system, which will cause
the moisture indicator's element to turn white or pink; if
this happens, notify your supervisor.
Change 3 3-92.3
