AIR-CONDITIONING - Circuit Diagram 24-27
Air conditioner relay
@,0.85-WB
El
Low pressure
switch
A-54 El
85-BW:0.85-BW ) To feed back carburetc
u control unit
A-25 [Refer to P.8-39.1
*20.85-BWr
*10.85-BWi& Vacuum solenoid
A-13 ++ valve
A-45
Condenser Condenser blower
blower motor motor relay
A
rl z-
BY
37W611 Magnetic
clutch
(compressor)
Remarks
(1) For information converning the ground points (exam-
ple.(l)m), refer to P.8-7.
(2) The symbols 0, 0, etc indicate that the wiring is
connected (using the same numerical symbol) to the
facing page (In other words, 0 on the right page is
connected to 0 on the left page.)
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AIR-CONDITIONING-Service Adiustment Procedures 24-31
FREEZE UP CONTROL
Evaporator freeze up is controlled by a thermistor attached to the
evaporator fins. The control is an electronic type and consists of
two parts_(thermo relay and thermistor.) It is connected to the
magnetic clutch of the compressor in series. When the tempera-
ture of the evaporator drops below 3°C (37.4”F), the compressor is
turned OFF.
To Test the Thermistor
(1) Jump the wire lead (LB to GB) of the connector portion.
(2) Press the air conditioner switch and blower switch on.
(3) Momentarily turn the ignition switch on (do not crank the en-
gine), listen for the clutch engaging.
(4) If the clutch does not engage, the low pressure switch,
water temperature switch wiring or fuse may be faulty.
(5) If the clutch operates, replace the thermostat.
WATER TEMPERATURE SWITCH
The water temperature switch is located on the thermostat hous-
ing. The water temperature switch is connected to the clutch
in series. When the coolant temperature in the radiator
reaches above 113°C (235”F), it turns the compressor OFF.
This is to prevent engine overheating.
When the water temperature switch is activated and the clutch is
OFF, check the surface of the condenser and radiator, the belt
tension, and the coolant volume in the radiator, and return to the
normal condition.
To Test the Water Temperature Switch
(1) Remove wire from water temperature switch and jump lead
wires.
(2) Press the air conditioner switch and blower switch on.
(3) Momentarily turn the ignition switch on (do not crank the en-
gine), listen for the clutch engaging.
(4) If the clutch does not-engage, the fin thermistor, low pressure
switch, wiring or fuse may be faulty.
(5) If clutch engages, replace the switch.
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