Page 107 of 1807

N08744Sight Glass
AC0PZ-01
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-3
2151 Author: Date:
1997 SUPRA (RM502U)
ON-VEHICLE INSPECTION
1. INSPECT REFRIGERANT VOLUME
Observe the sight glass on the liquid tube.
Test conditions:
Running engine at 1,500 rpm
Blower speed control switch at ºHIº position
A/C switch ON
Temperature control dial at ºCOOLº position
Fully open the doors
ItemSymptomAmount of refrigerantRemedy
1Bubbles present in sight glassInsufficient*
(1) Check for gas leakage with gas leak de-
tector and repair if necessary
(2) Add refrigerant until bubbles disappear
2No bubbles present in sight glassNone, sufficient or too muchRefer item 3 and 4
3No temperature difference between com-
pressor inlet and outletEmpty or nearly empty
(1) Check for gas leakage with gas leak de-
tector and repair if necessary
(2) Add refrigerant until bubbles disappear
4Temperature between compressor inlet and
outlet is noticeably differentCorrect or too muchRefer to items 5 and 6
5Immediately after air conditioning is turned
off, refrigerant in sight glass stays clearToo much
(1) Discharge refrigerant
(2) Evacuate air and charge proper amount
of purified refrigerant
6When air conditioning is turned off, refriger-
ant foams and then stays clearCorrect-
*: Bubbles in the sight glass with ambient temperatures higher than usual can be considered normal if cooling
is sufficient.
Page 108 of 1807
I01386
AC-4
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
2152 Author: Date:
1997 SUPRA (RM502U)
2. INSPECT REFRIGERANT PRESSURE WITH MAN-
IFOLD GAUGE SET
This is a method in which the trouble is located by using a man-
ifold gauge set. Read the manifold gauge pressure when these
conditions are established.
Test conditions:
Temperature at the air inlet with the switch set
at RECIRC is 30 - 35 °C (86 - 95 °F)
Engine running at 1500 rpm
Blower speed control switch at ºHIº position
Temperature control dial on ºCOOLº position
HINT:
It should be noted that the gauge indications may vary slightly
due to ambient temperature conditions.
(1) Normally functioning refrigeration system.
Gauge reading:
Low pressure side:
0.15 - 0.25 MPa (1.5 - 2.5 kgf/cm
2)
High pressure side:
1.37 - 1.57 MPa (14 - 16 kgf/cm
2)
Page 111 of 1807

I01390
Condition: Insufficient cooling
I01392
Condition: Insufficient cooling
NOTE : These gauge indica-
tions are shown when the
refrigeration system has
been opened and the refrig-
erant charged without vacu-
um purging.
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-7
2155 Author: Date:
1997 SUPRA (RM502U)
(6) Refrigerant overcharged or insufficient cooling of
condenser
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on both low
and high pressure sides
No air bubbles seen through the
sight glass even when the engine
rpm is lowered Unable to develop sufficient per-
formance due to excessive refrig-
eration system
Insufficient cooling of condenser Excessive refrigerant in
cycle " refrigerant over charged
Condenser cooling " condenser
fins clogged of condenser fan
faulty
(1) Clean condenser
(2) Check condenser fan motor
operation
(3) If (1) and (2) are in normal
state, check amount of refrigerant
Charge proper amount of refriger-
ant
(7) Air present in refrigeration system
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on both low
and high pressure sides
The low pressure piping hot to
touch
Bubbles seen in sight glass
Air entered in refrigeration system
Air present in refrigeration sys-
tem
Insufficient vacuum purging
(1) Check compressor oil to see if
it is dirty or insufficient
(2) Evacuate air and charge new
refrigerant
Page 113 of 1807

- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-9
2157 Author: Date:
1997 SUPRA (RM502U)
3. INSPECT IDLE-UP SPEED
(a) Warm up engine
(b) Inspect idle-up speed when the these conditions are es-
tablished.
Test conditions:
Blower speed control switch at ºHIº position
Temperature control dial at ºCOOLº position
A/C switch ON
Put gear shift in neutral
2JZ-GE (M/T)
Magnetic clutch conditionIdle-up speed
Not engaged700 ± 50 rpm
Engaged900 ± 50 rpm
If idle speed is not as specified, check the IAC valve and air in-
take system.
2JZ-GE (A/T)
Magnetic clutch conditionIdle-up speed
Not engaged700 ± 50 rpm
Egagedn800 ± 50 rpm
If idle speed is not as specified, check the IAC valve and air in-
take system.
2JZ-GTE
magnetic clutch conditionIdle-up speed
Not engaged650 ± 50 rpm
Engaged800 ± 50 rpm
If idle speed is not as specified, check the IAC valve and air in-
take system.
4. INSPECT FOR LEAKAGE OF REFRIGERANT
(a) Perform in these conditions:
Stop engine.
Secure good ventilation (If the gas leak detector
may not react to volatile gases which are not refrig-
erant, such as evaporated gasoline and exhaust
gas.)
Repeat the test 2 or 3 times.
Make sure that there is some refrigerant remaining
in the refrigeration system.
When compressor is OFF: approx. 392 - 588 kPa
(4 - 6 kgf/ cm
2, 57 - 85 psi)
Page 116 of 1807
N13790
Low Pressure
Service Valve
High Pressure
Service Valve
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC-13
2161 Author: Date:
1997 SUPRA (RM502U)
3. CHARGE REFRIGERANT INTO REFRIGERANT SYS-
TEM
If there is no leak after refrigerant leak check, charge the proper
amount of refrigerant into refrigeration system.
CAUTION:
Never run the engine when charging the system
through the high pressure side.
Do not open the low pressure hand a valve when the
system is being charged with liquid refrigerant.
(a) Open the high pressure hand valve fully.
(b) Charge specified amount of refrigerant, then close the
high pressure hand valve.
HINT:
A fully charged system is indicated by the sight glass being free
of any bubbles.
4. REMOVE MANIFOLD GAUGE SET
(a) Close both hand valves of manifold gauge set.
(b) Disconnect the quick disconnect adapters from the ser-
vice valves.
5. INSTALL CAPS TO SERVICE VALVES ON REFRIGER-
ANT LINES
Page 117 of 1807
AC0Q2-01
Z18473
Pressure Switch
ReceiverRadiator
Fan Relay
No. 1
Compressor
Radiator
Fan Relay
No. 2Junction Block No. 2
Magnetic Clutch Relay
Reater Main Relay
Ambient Temperature
Sensor
Air Conditioning Amplifier
Solar Sensor
Room Temperature
SensorAir Conditioning
Control Assembly
Evaporator
Expansion Valve
Water Valve
Heater Radiaor
Air Outlet ServomotorAir Inlet
Servomotor
Blower Motor
Blower Motor
Control Relay
Evaporator Temperature Sensor
Air Mix Servomotor
Engine Coolant Temperature Sensor AC-14
- AIR CONDITIONINGAIR CONDITIONING SYSTEM
2162 Author: Date:
1997 SUPRA (RM502U)
LOCATION
Page 123 of 1807
N11671
Defroster Nozzle
Water Valve CoverPlate
Water Valve
Heater Radiator
A/C Unit
Block Joint
Blower Motor
Control Relay
Blower Motor
Lower CaseEvaporator
Expansion
Valve Air Inlet
Servomotor
Evaporator Temperature
Sensor Heater Air Duct
Evaporator CoverVent Air DuctEngine Coolant
Temperature
SensorAir Outlet
ServomotorAir Mix
Servomotor AC-24
- AIR CONDITIONINGAIR CONDITIONING UNIT
2172 Author: Date:
1997 SUPRA (RM502U)
Page 124 of 1807
AC0QC-01
N08378
I03519
- AIR CONDITIONINGAIR CONDITIONING UNIT
AC-25
2173 Author: Date:
1997 SUPRA (RM502U)
REMOVAL
1. DISCHARGE REFRIGERANT FROM REFRIGERANT
SYSTEM
HINT:
At the time of installation, please refer to the following item.
Evacuate air from refrigeration system.
Charge system with the refrigerant and inspect for leakage of
refrigerant.
Specified amount: 700 ± 50 g (24.96 ± 1.76 oz.)
2. DRAIN ENGINE COOLANT FROM RADIATOR
HINT:
It is not necessary to drain out all coolant.
3. REMOVE THESE PARTS:
(a) Engine wire harness bracket mounting bolt
(b) Brake tube bracket mounting bolts
4. DISCONNECT WATER HOSE FROM HEATER RADIA-
TOR PIPES
(a) Using priers, grip the claw of the hose clip and slide the
clip along the hose.
(b) Disconnect the water hoses from heater radiator pipes.
5. REMOVE INSULATOR RETAINER
Remove the 2 bolts and the insulator retainer.