check engine TOYOTA SUPRA 1995 Service User Guide

6. REFRIGERANT OVERCHARGE OR INSUFFICIENT COOLING OF CONDENSER
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
(1) Clean condenser
(2) Check fan motor
operation
(3) If (1) and (2) are in
normal state, check
amount of refrigerant
Charge proper amount
of refrigerant
Pressure too high on both
low and high pressure
sides

No air bubbles seen
through the sight of glass
even when the engine
rpm is lowered.
Unable to develop
sufficient performance
due to excessive
refrigerant in system

Insufficient cooling of
condenser
Excessive refrigerant in
in cycle " refrigerant
overcharged

Condenser cooling
insufficient " condenser
fins clogged or fan motor
faulty
Condition: Insufficient Cooling
7. AIR PRESENT IN REFRIGERATION SYSTEM
Condition: insufficient cooling
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
(1) Check compressor oil to
see if dirty or insufficient
(2) Evacuate air and charge
new refrigerant
Pressure too high on both
low and high pressure
sides

The low pressure piping is
hot to the touch

Bubbles seen in sight
glass
Air entered in
refrigeration system
Air present in
refrigeration system
NOTE: These gauge indications are shown when the refrigeration
system has been opened and the refrigerant charged without
vacuum purging.

Insufficient vacuum
purging
AC±74± AIR CONDITIONING SYSTEMTROUBLESHOOTING

REFRIGERANT VOLUME
REFRIGERANT VOLUME INSPECTION
1. RUN ENGINE AT APPROX. 1,500 RPM
2. SET TEMPERATURE CONTROL AT MAX. COOL
3. SET BLOWER SWITCH AT ºHIº
4. SET AIR INLET CONTROL AT ºRECIRCº
5. TURN A/C SWITCH ON
6. FULLY OPEN DOORS
7. INSPECT AMOUNT OF REFRIGERANT
Observe the sight glass on the liquid tube.
 Item Symptom Amount of refrigerant Remedy
 
 
 
 
1
 
 
 
 
Bubbles present in sight glass
 
 
 
 
Insufficient*
 
 
 
 
(1) Check for gas leakage with gas leak
tester and repair if necessary
(2) Add refrigerant until bubbles dis±
appear
 
 2
 
 No bubbles present in sight glass
 
 
None, sufficient or too
much 
 Refer to items 3 and 4
 
 
 
 
3
 
 
 
 
No temperature difference between
compressor inlet and outlet
 
 
 
 
Empty or nearly empty
 
 
 
 
(1) Check for gas leakage with gas leak
tester and repair if necessary
(2) Add refrigerant until bubbles disap-
pear
 
 4 
 
Temperature between compressor
inlet and outlet is noticeably different 
 Correct or too much 
 Refer to items 5 and 6
 
 
 
5
 
 
 
Immediately after air conditioning is
turned off, refrigerant in sight glass
stays clear 
 
 
Too much
 
 
 
(1) Discharge refrigerant
(2) Evacuate air and charge proper
amount of purified refrigerant
 
 
 
6
 
 
 
When air conditioning is turned off,
refrigerant foams and then stays
clear 
 
 
Correct
 
 
 
±±
* Bubbles in the sight glass with ambient temperatures higher
than usual can be considered normal if cooling is sufficient.
REFRIGERANT CHARGE VOLUME
Specified amount:
700 + 50 g (24.96 + 1.76 oz.)
AC±76± AIR CONDITIONING SYSTEMREFRIGERANT VOLUME

DRIVE BELT TENSION
DRIVE BELT TENSION INSPECTION
1. INSPECT DRIVE BELT'S INSTALLATION CONDITION
Check that drive belt fits properly in the ribbed grooves.
2. INSPECT DRIVE BELT TENSION
Check that the tension is within A range on the auto tensioner
scale.
If the tension is not within the A range on the scale, replace
the belt with a new one.
HINT: When replacing the drive belt with a new one, the belt's
tension should be within the B range on the belt tensioner
scale.
IDLE±UP SPEED
IDLE UP SPEED INSPECTION
1. WARM UP ENGINE
2. INSPECT IDLE SPEED
Put gear shift in neutral.
2JZ±GE (M/T)
 
Magnetic clutch condition 
Standard idle speed (RPM)
 Not engaged Approx. 700
 Engaged Approx. 900
2JZ±GE (A/T)
 Magnetic clutch condition Standard idle speed (RPM) Not engaged Approx. 700 
 Engaged
 
 Approx. 800
2JZ±GTE
 Magnetic clutch condition Standard idle speed (RPM)
 Not engaged Approx. 650 Engaged Approx. 800
± AIR CONDITIONING SYSTEMDRIVE BELT TENSIONAC±77

AIR CONDITIONING UNIT ASSEMBLY
Assembly is in the reverse order of disassembly.
AIR CONDITIONING UNIT INSTALLATION
Installation is in the reverse order of removal.
COMPRESSOR
ON±VEHICLE INSPECTION
Magnetic Clutch:
(See page AC±62)
Compressor:
1. INSTALL MANIFOLD GAUGE SET
(See page AC±11)
2. START ENGINE
3. INSPECT COMPRESSOR FOR METALLIC SOUND
Check that there is metallic sound from the compressor when
the A/C switch is turned ON.
If a metallic sound is heard, replace the compressor assem-
bly.
4. INSPECT PRESSURE OF REFRIGERATION SYSTEM
See ºRefrigeration System Inspection with Manifold Gauge
Setº on page AC±71.
5. STOP ENGINE
6. INSPECT VISUALLY FOR LEAKAGE OF REFRIGERANT
FROM SAFETY SEAL
If there is any leakage, replace the compressor assembly.
± AIR CONDITIONING SYSTEMAIR CONDITIONING UNITAC±85

(c) Check the clearance between the pressure plate and rotor,
then connect the negative (±) terminal of the battery.
Standard clearance:
0.5 + 0.15 mm (0.020 + 0.0059 in.)
If the clearance is not within specification, adjust the clear-
ance using shims to obtain the standard clearance.
Shim Thickness:
0.1 mm (0.004 in.)
0.3 mm (0.012 in.)
0.5 mm (0.020 in.)
COMPRESSOR INSTALLATION
1. INSTALL COMPRESSOR
(a) Install the stud bolt.
Torque: 26 NVm (265 kgfVcm, 19 ftVlbf)
(b) Install the compressor with 4 bolts and nut.
Torque: 52 NVm (530 kgfVcm, 38 ftVlbf)
(c) Connect the magnetic clutch connector.
(d) Install the engine under cover.
2. CONNECT DISCHARGE HOSE AND SUCTION HOSE TO
COMPRESSOR
NOTICE: Hoses should be connected immediately after
the caps have been removed.
Torque: 10 NVm (100 kgfVcm, 7 ftVlbf)
3. INSTALL POWER STEERING PUMP
Install the power steering pump with 2 bolts.
Torque: 58 NVm (590 kgfVcm, 43 ftVlbf)
4. INSTALL DRIVE BELT
5. INSTALL BATTERY
6. EVACUATE AIR IN REFRIGERATION SYSTEM AND
CHARGE WITREFRIGERANT
Specified amount:
700 + 50 g (24.96 + 1.76 oz.)
7. INSPECT FOR LEAKAGE OF REFRIGERANT
Using a gas leak tester, check for leakage of refrigerant.
If there is leakage, check the tightening torque at the joints.
8. INSPECT A/C OPERATION AC±90
± AIR CONDITIONING SYSTEMCOMPRESSOR

CONDENSER
ON±VEHICLE INSPECTION
1. INSPECT CONDENSER FINS FOR BLOCKAGE OR
DAMAGE
If fins are clogged, wash them with water and dry with com-
pressed air.
NOTICE: Be careful not to damage the fins.
If fins are bent, straighten them with a screwdriver or pliers.
2. INSPECT CONDENSER AND FITTING FOR LEAKAGE
Using a gas leak tester, check for leakage.
If there is leakage, check the tightening torque at the joints.
CONDENSER REMOVAL
1. DISCHARGE REFRIGERANT IN REFRIGERATION
SYSTEM
INSTALLATION HINT: Evacuate air from refrigeration sys-
tem.
Charge system with refrigerant and inspect for leakage of re-
frigerant.
Specified amount:
700 +50g (24.96 +1.76 oz.)
2. REMOVE BATTERY
3. REMOVE AIR CLEANER DUCT
Remove the bolt and the air cleaner duct.
4. REMOVE AIR CLEANER
(a) Remove the air cleaner cover.
(b) Remove the air cleaner hose.
(c) 2JZ±GTE:
Remove the No. 1 air hose.
(d) Remove the 3 bolts and 2 screws.
(e) Remove the air cleaner.
5. REMOVE NO.5 AIR HOSE CLAMP (2JZ±GTE)
(a) Remove the 2 bolts and clamp.
(b) Push the hose to engine side.
6. REMOVE FRONT BUMPER
(See page BO±88)
7. REMOVE RADIATOR SUPPORT UPPER SEAL
(See page AC±91)
8. REMOVE RECEIVER
(See page AC±91) AC±92
± AIR CONDITIONING SYSTEMCONDENSER

EXPANSION VALVE
ON±VEHICLE INSPECTION
1. CHECK QUANTITY OF GAS DURING REFRIGERATION
CYCLE
2. INSTALL MANIFOLD GAUGE SET
3. RUN ENGINE
Run the engine at 1,500 rpm for at least 5 minutes. Then
check that the high pressure reading is 1.371.57 MPa (14±16
kgf/cm
2, 199±228 psi).
4. CHECK EXPANSION VALVE
If the expansion valve is faulty, the low pressure reading will
drop to 0 kPa (0 kgf/cm
2, 0 psi).
HINT: When the low pressure drops to 0 kPa (0 kgf/cm
2, 0
psi), feel the receiver's IN and OUT sides for zero tempera-
ture difference.
EXPANSION VALVE REMOVAL
1. REMOVE EVAPORATOR
(See page AC±82)
2. REMOVE EXPANSION VALVE
Using a hexagon wrench, remove the 2 bolts and separate
the evaporator and expansion valve.
Torque: 5.4 NVm (55 kgfVcm, 48 in.Vlbf)
INSTALLATION HINT: Lubricate the new O±ring with com-
pressor oil and install the tubes.
EXPANSION VALVE INSTALLATION
Installation is in the reverse order of removal. AC±98
± AIR CONDITIONING SYSTEMEXPANSION VALVE

ELECTRIC COOLING FAN
ON±VEHICLE INSPECTION
Condenser Fan:
1. INSPECT CONDENCER
(a) Disconnect the fan connector.
(b) Connect battery and ammeter to the cooling fan connector.
(c) Check that the condenser fan rotates smoothly, and check
the reading on the ammeter.
Standard amperage:
6.0±7.4 A
(d) Reconect the fan connector.
2. CONNECT NEGATIVE (±) TERMINAL CABLE TO
BATTERY
Radiator Fan:
(See page EG±353)
COOLING FAN RELAYS INSPECTION
(See page EG±356)
ECT SWITCH
(in ENGINE RADIATOR)
(See page EG±356)
± AIR CONDITIONING SYSTEMELECTRIC COOLING FANAC±107

INTRODUCTIONGLOSSARY OF SAE AND TOYOTA TERMS -
IN-7
GLOSSARY OF SAE AND TOYOTA TERMS
This glossary lists all SAE-J1930 terms and abbreviations used in this manual in compliance with SAE
recommendations, as well as their Toyota equivalents.
SAE
ABBREVIATIONSSAE TERMSTOYOTA TERMS
( )--ABBREVIATIONS
A/CAir ConditioningAir Conditioner
ACLAir CleanerAir Cleaner
AIRSecondary Air InjectionAir Injection (AI)
APAccelerator Pedal-
B+Battery Positive Voltage+B, Battery Voltage
BAROBarometric Pressure-
CACCharge Air CoolerIntercooler
CARBCarburetorCarburetor
CFIContinuous Fuel Injection-
CKPCrankshaft PositionCrank Angle
CLClosed LoopClosed Loop
CMPCamshaft PositionCam Angle
CPPClutch Pedal Position-
CTOXContinuous Trap Oxidizer-
CTPClosed Throttle Position-
DFIDirect Fuel Injection (Diesel)Direct Injection (DI)
DIDistributor Ignition-
DLC1
DLC2
DLC3Data Link Connector 1
Data Link Connector 2
Data Link Connector 31: Check Connector
2: Toyota Diagnosis Communication Link (TDCL)
3: OBD II Diagnostic Connector
DTCDiagnostic Trouble CodeDiagnostic Code
DTMDiagnostic Test Mode-
ECLEngine Control Level-
ECMEngine Control ModuleEngine ECU (Electronic Control Unit)
ECTEngine Coolant TemperatureCoolant Temperature, Water Temperature (THW)
EEPROMElectrically Erasable Programmable Read Only
MemoryElectrically Erasable Programmable Read Only Memory
(EEPROM),
Erasable Programmable Read Only Memory(EPROM)
EFEEarly Fuel EvaporationCold Mixture Heater (CMH), Heat Control Valve (HCV)
EGRExhaust Gas RecirculationExhaust Gas Recirculation (EGR)
EIElectronic IgnitionToyota Distributorless Ignition (TDI)
EMEngine ModificationEngine Modification (EM)
EPROMErasable Programmable Read Only MemoryProgrammable Read Only Memory (PROM)
EVAPEvaporative EmissionEvaporative Emission Control (EVAP)
FCFan Control-
FEEPROMFlash Electrically Erasable Programmable
Read Only Memory-
FEPROMFlash Erasable Programmable Read Only Memory-
FFFlexible Fuel-
FPFuel PumpFuel Pump
GENGeneratorAlternator
GNDGroundGround (GND)
HO2SHeated Oxygen SensorHeated Oxygen Sensor (HO2S)
IN016-02

INTRODUCTIONGLOSSARY OF SAE AND TOYOTA TERMS -
IN-8
IACIdle Air ControlIdle Speed Control (ISC)
IATIntake Air TemperatureIntake or Inlet Air Temperature
ICMIgnition Control Module-
IFIIndirect Fuel InjectionIndirect Injection
IFSInertia Fuel-Shutoff-
ISCIdle Speed Control-
KSKnock SensorKnock Sensor
MAFMass Air FlowAir Flow Meter
MAPManifold Absolute PressureManifold Pressure
Intake Vacuum
MCMixture Control
Electric Bleed Air Control Valve (EBCV)
Mixture Control Valve (MCV)
Electric Air Control Valve (EACV)
MDPManifold Differential Pressure-
MFIMultiport Fuel InjectionElectronic Fuel Injection (EFI)
MILMalfunction Indicator LampCheck Engine Light
MSTManifold Surface Temperature-
MVZManifold Vacuum Zone-
NVRAMNon-V olatile Random Access Memory-
O2SOxygen SensorOxygen Sensor, O2 Sensor (O2S)
OBDOn-Board DiagnosticOn-Board Diagnostic (OBD)
OCOxidation Catalytic ConverterOxidation Catalyst Converter (OC), CCo
OPOpen LoopOpen Loop
PAIRPulsed Secondary Air InjectionAir Suction (AS)
PCMPowertrain Control Module-
PNPPark/Neutral Position-
PROMProgrammable Read Only Memory-
PSPPower Steering Pressure-
PTOXPeriodic Trap OxidizerDiesel Particulate Filter (DPF)
Diesel Particulate Trap (DPT)
RAMRandom Access MemoryRandom Access Memory (RAM)
RMRelay Module-
ROMRead Only MemoryRead Only Memory (ROM)
RPMEngine SpeedEngine Speed
SCSuperchargerSupercharger
SCBSupercharger Bypass-
SFISequential Multiport Fuel InjectionElectronic Fuel Injection (EFI), Sequential Injection
SPLSmoke Puff Limiter-
SRIService Reminder Indicator-
SRTSystem Readiness Test-
STScan Tool-
TBThrottle BodyThrottle Body
TBIThrottle Body Fuel InjectionSingle Point Injection
Central Fuel Injection (Ci)
TCTurbochargerTurbocharger
TCCTorque Converter ClutchTorque Converter
TCMTransmission Control ModuleTransmission ECU (Electronic Control Unit)
TPThrottle PositionThrottle Position
TRTransmission Range-