sensor TOYOTA SUPRA 1995 Service Repair Manual

IF VEHICLE IS EQUIPPED WITH MOBILE
COMMUNICATION SYSTEM
For vehicles with mobile communication systems such as
two±way radios and cellular telephones, observe the follow-
ing precautions.
(1) Install the antenna as far as possible away from the ECM,
ECU and sensors of the vehicle's electronic system.
(2) Install the antenna feeder at least 20 cm (7.87 in.) away from
the ECM, ECU and sensors of the vehicle's electronics
systems. For details about ECM, ECU and sensors locations,
refer to the section on the applicable component.
(3) Do not wind the antenna feeder together with the other
wiring. As much as possible, also avoid running the antenna
feeder parallel with other wire harnesses.
(4) Confirm that the antenna and feeder are correctly adjusted.
(5) Do not install powerful mobile communications system. IN±18
± INTRODUCTIONPRECAUTION

[2] SYMPTOM CONFIRMATION AND DIAGNOSTIC TROUBLE CODE CHECK
The diagnostic system in the TOYOTA SUPRA fulfills various functions. The first function is the Diagnostic
Trouble Code Check in which a malfunction in the signal circuits to the ECU is stored in code in the ECU memory
at the time of occurrence, to be output by the technician during troubleshooting. Another function is the Input
Signal Check which checks if the signals from various switches are sent to the ECU correctly. The air condition-
ing system has an Actuator Check function whereby the ECU automatically operates the actuators of the damp-
er and blowermotor, etc. to check the operation. By using these check functions, the problem areas can be nar-
rowed down quickly and troubleshooting can be performed effectively. Diagnostic functions are incorporated
in the following systems in the TOYOTA SUPRA.
 
 System
 
 
Diagnostic Trouble
Code Check 
 
Input Signal Check
(Sensor Check) 
 
Other Diagnosis
Function
 
 
 
 
 
 
Engine
Automatic Transmission
Anti±Lock Brake
Traction Control (Option)
Supplemental Restraint System
Cruise Control
Air Conditioning 
 
 
 
 
 
O (with Test Mode)
O (with Test Mode)
O
O
O
O
O 
 
 
 
 
 
O
O
O
O
O
O 
 
 
 
 
 Actuator Check
In diagnostic trouble code check, it is very important to determine whether the problem indicated by the diagnos-
tic trouble code is still occurring or occurred in the past but returned to normal at present. In addition, it must
be checked in the problem symptom check whether the malfunction indicated by the diagnostic trouble code
is directly related to the problem symptom or not. For this reason, the diagnostic trouble codes should be
checked before and after the symptom confirmation to determine the current conditions, as shown in the table
below. If this is not done, it may, depending on the case, result in unnecessary troubleshooting for normally oper-
ating systems, thus making it more difficult to locate the problem, or in repairs not pertinent to the problem.
Therefore, always follow the procedure in correct order and perform the diagnostic trouble code check.
DIAGNOSTIC TROUBLE CODE CHECK PROCEDURE
 
 
 
Diagnostic Trouble
Code Check (Make a
note of and then clear) 
 
 
Confirmation of
symptoms 
 
 
Diagnostic Trouble
Code Check 
 
 
Problem Condition
 
 
Diagnostic
Trouble Code
Display 
 
Problem symptoms
exist 
 
Same Diagnostic
trouble code is dis-
played 
 
Problem is still occurring in the diagnos-
tic circuit
 
 
 
 
 
%
 
 
 
 
 
 
 
 
 
 
Normal code is dis-
played 
 
 
 
 
The problem is still occurring in a place
other than in the diagnostic circuit. (The
diagnostic trouble code displayed first is
either for a past problem or it is a sec-
ondary problem.)
 
 %
 
 
No problem
symptoms exist 
 
 
 
The problem occurred in the diagnostic
circuit in the past.
 
 
Normal Code Display
%
 
 
Problem symptoms
exist 
 
Normal code is dis-
played 
 
The problem is still occurring in a place
other than in the diagnostic circuit.
 
 %
 
 
No problem
symptoms exist 
 
Normal code is dis-
played 
 
The problem occurred in a place other
than in the diagnostic circuit in the past.
IN±22± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS

[3] SYMPTOM SIMULATION
The most difficult case in troubleshooting is when there are no problem symptoms occurring. In such cases, a
thorough customer problem analysis must be carried out, then simulate the same or similar conditions and envi-
ronment in which the problem occurred in the customer's vehicle. No matter how much experience a technician
has, or how skilled he may be, if he proceeds to troubleshoot without confirming the problem symptoms he will
tend to overlook something important in the repair operation and make a wrong guess somewhere, which will
only lead to a standstill. For example, for a problem which only occurs when the engine is cold, or for a problem
which occurs due to vibration caused by the road during driving, etc., the problem can never be determined so
long as the symptoms are confirmed with the engine hot condition or the vehicle at a standstill. Since vibration,
heat or water penetration (moisture) are likely causes for problems which are difficult to reproduce, the symptom
simulation tests introduced here are effective measures in that the external causes are applied to the vehicle
in a stopped condition.
Important Points in the Symptom Simulation Test
In the symptom simulation test, the problem symptoms should of course be confirmed, but the problem area
or parts must also be found out. To do this, narrow down the possible problem circuits according to the symptoms
before starting this test and connect a tester beforehand. After that, carry out the symptom simulation test, judg-
ing whether the circuit being tested is defective or normal and also confirming the problem symptoms at the
same time. Refer to the matrix chart of problem symptoms for each system to narrow down the possible causes
of the symptom.
VIBRATION METHOD: When vibration seems to be the major cause.
CONNECTORS
Slightly shake the connector vertically and horizontally.
WIRE HARNESS
Slightly shake the connector vertically and horizontally
.
The connector joint, fulcrum of the vibration, and body
through portion are the major areas to be checked thor-
oughly.
PARTS AND SENSORS
Apply slight vibration with a finger to the part of the sen-
sor considered to be the problem cause and check if the
malfunction occurs.
HINT: Applying strong vibration to relays may result in
open relays. IN±24
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS

HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION
PROCEDURE
1. For troubleshooting, diagnostic trouble code charts or problem symptom charts are provided for each
circuit with detailed inspection procedures on the following pages.
2. When all the component parts, wire harnesses and connectors of each circuit except the ECU are found
to be normal in troubleshooting, then it is determined that the problem is in the ECU.
Accordingly, if diagnosis is performed without the problem symptoms occurring, the instruction will be to
check and replace the ECU, even if the problem is not in the ECU. So, always confirm that the problem
symptoms are occurring, or proceed with inspection while using the symptom simulation method.
3. The instructions ºCheck wire harness and connectorº and ºCheck and replace ECUº which appear in the
inspection procedure, are common and applicable to all diagnostic trouble codes. Follow the procedure
outlined below whenever these instructions appear.
Check Wire Harness and Connector
The problem in the wire harness or connector is an open circuit or a short circuit.
OPEN CIRCUIT:
This could be due to a disconnected wire harness, faulty contact in the connector, a connector terminal pulled
out, etc.
HINT:
1. It is rarely the case that a wire is broken in the middle of it. Most cases occur at the connector. In particular,
carefully check the connectors of sensors and actuators.
2. Faulty contact could be due to rusting of the connector terminals, to foreign materials entering terminals
or a drop in the contact pressure between the male and female terminals of the connector. Simply
disconnecting and reconnecting the connectors once changes the condition of the connection and may
result in a return to normal operation.
Therefore, in troubleshooting, if no abnormality is found in the wire harness and connector check, but the
problem disappears after the check, then the cause is considered to be in the wire harness or connectors.
SHORT CIRCUIT:
This could be due to a short circuit between the wire harness and the body ground or to a short inside the switch,
etc.
HINT:
wWhen there is a short between the wire harness and body ground, check thoroughly whether the wire
harness is caught in the body or is clamped properly. IN±30
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS

1. CONTINUITY CHECK (OPEN CIRCUIT CHECK)
(1) Disconnect the connectors at both ECU and sensor sides.
(2) Measure the resistance between the applicable terminals of
the connectors.
Resistance: 1
or less
HINT:
wMeasure the resistance while lightly shaking the wire
harness vertically and horizontally.
wWhen tester probes are inserted into a connector, insert
the probes from the back. For waterproof connectors in
which the probes cannot be inserted from the back, be
careful not to bend the terminals when inserting the
tester probes.
2. RESISTANCE CHECK (SHORT CIRCUIT CHECK)
(1) Disconnect the connectors at both ends.
(2) Measure the resistance between the applicable terminals of
the connectors and body ground. Be sure to carry out this
check on the connectors on both ends.
Resistance: 1 M
or higher
HINT: Measure the resistance while lightly shaking the wire
harness vertically and horizontally.
3. VISUAL CHECK AND CONTACT PRESSURE CHECK
(a) Disconnect the connectors at both ends.
(b) Check for rust or foreign material, etc. on the terminals of the
connectors.
(c) Check crimped portions for looseness or damage and check
if the terminals are secured in the lock position.
HINT: The terminals should not come out when pulled lightly.
(d) Prepare a test male terminal and insert it in the female
terminal, then pull it out.
HINT: When the test terminal is pulled out more easily than
others, there may be poor contact in that section.
± INTRODUCTIONHOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMSIN±31

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 ABBREVI±
ATIONS 
 SAE TERMS
 
 
TOYOTA TERMS
( ) ±± ABBREVIATIONS
 A/C Air Conditioning Air Conditioner
 ACL Air Cleaner Air Cleaner
AIRSecondary Air InjectionAir Injection (AI) AP Accelerator Pedal ± B+ Battery Positive Voltage +B, Battery Voltage BARO Barometric Pressure ±
 CAC Charge Air Cooler Intercooler
 CARB Carburetor Carburetor
 CFI Continuous Fuel Injection ±
 CKP Crankshaft Position Crank Angle
CLClosed LoopClosed Loop CMP Camshaft Position Cam Angle CPP Clutch Pedal Position ±
 CTOX Continuous Trap Oxidizer ±
 CTP Closed Throttle Position Idle ON (IDL ON)
 DFI Direct Fuel Injection (Diesel) Direct Injection (DI)
 DI Distributor Ignition ±
 
 
DLC1
DLC2
DLC3 
 
Data Link Connector 1
Data Link Connector 2
Data Link Connector 3 
 
1: Check Connector
2: Toyota Diagnosis Comunication Link (TDCL)
3: OBD II Diagnostic Connector
 DTC Diagnostic Trouble Code Diagnostic Code
 DTM Diagnostic Test Mode ±
 ECL Engine Control Level ±
 ECM Engine Control Module Engine ECU (Electronic Control Unit)
 ECT Engine Coolant Temperature Coolant Temperature, Water Temperature
(THW)
 
 
 
 
EEPROM
 
 
 
 
Electrically Erasable Programmable Read Only
Memory
 
 
 
 
Electrically Erasable Programmable Read Only
Memory (EEPROM),
Erasable Programmable Read Only Memory
(EPROM)
 
 
EFE 
 
Early Fuel Evaporation 
 
Cold Mixture Heater (CMH), Heat Control Valve
(HCV)
EGRExhaust Gas RecirculationExhaust Gas Recirculation (EGR) EI Electronic Ignition Toyota Distributorless Ignition (TDI) EM Engine Modification Engine Modification (EM) EPROM Erasable Programmable Read Only Memory Programmable Read Only Memory (PROM)
 EVAP Evaporative Emission Evaporative Emission Control (EVAP)
 FC Fan Control ±
 FEEPROM Flash Electrically Erasable Programmable
Read Only Memory ±
 
 FEPROM
 
 Flash Erasable Programmable Read Only
Memory 
 ±
 FF Flexible Fuel ±
 FP Fuel Pump Fuel Pump
 GEN Generator Alternator
 GND Ground Ground (GND)
HO2SHeated Oxygen SensorHeated Oxygen Sensor (HO2S)
± INTRODUCTIONGLOSSARY OF SAE AND TOYOTA TERMSIN±39

 IAC Idle Air Control Idle Speed Control (ISC)
IATIntake Air TemperatureIntake or Inlet Air Temperature ICM Ignition Control Module ± IFI Indirect Fuel Injection Indirect Injection IFS Inertia Fuel±Shutoff ±
 ISC Idle Speed Control ±
 KS Knock Sensor Knock Sensor
 MAF Mass Air Flow Air Flow Meter
 MAP Manifold Absolute Pressure Manifold Pressure
Intake Vacuum
 
 
 
MC
 
 
 
Mixture Control
 
 
 
Electric Bleed Air Control Valve (EBCV)
Mixture Control Valve (MCV)
Electric Air Control Valve (EACV)
 MDP Manifold Differential Pressure ±
 MFI Multiport Fuel Injection Electronic Fuel Injection (EFI)
MILMalfunction Indicator LampCheck Engine Light MST Manifold Surface Temperature ± MVZ Manifold Vacuum Zone ± NVRAM Non±Volatile Random Access Memory ±
 O2S Oxygen Sensor Oxygen Sensor, O2 Sensor (O2S)
 OBD On±Board Diagnostic On±Board Diagnostic (OBD)
 OC Oxidation Catalytic Converter Oxidation Catalyst Converter (OC), CCo
OPOpen LoopOpen Loop PAIR Pulsed Secondary Air Injection Air Suction (AS) PCM Powertrain Control Module ± PNP Park/Neutral Position ±
 PROM Programmable Read Only Memory ±
 PSP Power Steering Pressure ±
 
 
PTOX 
 
Periodic Trap Oxidizer 
 
Diesel Particulate Filter (DPF)
Diesel Particulate Trap (DPT)
RAMRandom Access MemoryRandom Access Memory (RAM) RM Relay Module ± ROM Read Only Memory Read Only Memory (ROM) RPM Engine Speed Engine Speed
 SC Supercharger Supercharger
 SCB Supercharger Bypass ±
 SFI Sequential Multiport Fuel Injection Electronic Fuel Injection (EFI), Sequential Injec-
tion
 SPL Smoke Puff Limiter ± SRI Service Reminder Indicator ± SRT System Readiness Test ±
 ST Scan Tool ±
 TB Throttle Body Throttle Body
 TBI Throttle Body Fuel Injection Single Point Injection
Central Fuel Injection (Ci)
 TC Turbocharger Turbocharger TCC Torque Converter Clutch Torque Converter TCM Transmission Control Module Transmission ECU (Electronic Control Unit)
 TP Throttle Position Throttle Position
 TR Transmission Range ±
IN±40± INTRODUCTIONGLOSSARY OF SAE AND TOYOTA TERMS

 
 
TVV 
 
Thermal Vacuum Valve 
 
Bimetallic Vacuum Switching Valve (BVSV)
Thermostatic Vacuum Switching Valve (TVSV)
 TWC Three±Way Catalytic Converter Three±Way Catalytic (TWC)
CC
RO 
TWC+OC
 
Three±Way + Oxidation Catalytic Converter
 
CCR + CCo 
VA F
 
Volume Air Flow
 
Air Flow Meter 
VR
 
Voltage Regulator
 
Voltage Regulator 
VSS
 
Vehicle Speed Sensor
 
Vehicle Speed Sensor (Read Switch Type) 
WOT
 
Wide Open Throttle
 
Full Throttle 
WU±OC
 
Warm Up Oxidation Catalytic Converter
 
± 
WU±TWC
 
Warm Up Three±Way Catalytic Converter
 
Manifold Converter 
3GR
 
Third Gear
 
± 
4GR
 
Fourth Gear
 
±
± INTRODUCTIONGLOSSARY OF SAE AND TOYOTA TERMSIN±41

OIL PUMP REMOVAL
HINT: When repairing the oil pump, the oil pan and strainer
should be removed and cleaned.
1. REMOVE ENGINE WITH TRANSMISSION
(See components for engine removal and installation)
2. SEPARATE ENGINE AND TRANSMISSION
(See components for engine & transmission separation
and assembly)
3. INSTALL ENGINE TO ENGINE STAND FOR REMOVAL
4. 2JZ±GTE:
REMOVE GENERATOR
5. 2JZ±GTE:
REMOVE CRANKSHAFT POSITION SENSOR
(a) Disconnect the sensor connector from the bracket.
(b) Disconnect the sensor connector from the wiring connector.
(c) Disconnect the wire clamp from the cylinder block.
(d) Remove the bolt and position sensor.
6. REMOVE TIMING BELT
(See steps 4 to 8 in timing belt removal in Engine Me-
chanical)
7. 2JZ±GTE M/T:
REMOVE DRIVE BELT TENSIONER BRACKET
Remove the 2 nuts and tensioner bracket.
8. REMOVE IDLER PULLEY
(See step 15 in timing belt removal in Engine Mechanical)
9. REMOVE CRANKSHAFT TIMING PULLEY
(See step 17 in timing belt removal in Engine Mechanical)
10. REMOVE OIL DIPSTICK AND GUIDE ASSEMBLY
(a) Remove the bolt.
(b) Pull out the dipstick guide together with the dipstick.
(c) Remove the O±ring from the dipstick guide.
11. REMOVE OIL LEVEL SENSOR
(a) Disconnect the level sensor connector.
(b) Remove the 4 bolts and level sensor.
(c) Remove the gasket from the level sensor.
NOTICE: Be careful not to drop the oil level sensor when re-
moving it.
± ENGINELUBRICATION SYSTEMEG±367

6. INSTALL OIL STRAINER
Install a new gasket and the oil strainer with the bolt and 2
nuts.
Torque: 8.8 NVm (90 kgfVcm, 78 in.Vlbf)
7. INSTALL NO.2 OIL PAN
(a) Remove any old packing (FIPG) material and be careful not
to drop any oil on the contact surfaces of the No.1 and No.2
oil pans.
wUsing a razor blade and gasket scraper, remove all the
old packing (FIPG) material from the gasket surfaces
and sealing groove.
wThoroughly clean all components to remove all the
debris.
wUsing a non±residue solvent, clean both sealing
surfaces.
NOTICE: Do not use a solvent which will affect the painted sur-
faces.
(b) Apply seal packing to the No.2 oil pan as shown in the
illustration.
Seal packing:
Part No.08826±00080 or equivalent
wInstall a nozzle that has been cut to a 3±4 mm
(0.12±0.16 in.) opening.
HINT: Avoid applying an excessive amount to the surface.
wParts must be assembled within 5 minutes of
application. Otherwise the material must be removed
and reapplied.
wImmediately remove nozzle from the tube and reinstall
cap.
(c) Install the No.2 oil pan with the 14 bolts and 2 nuts.
Torque: 8.8 NVm (90 kgfVcm, 78 in.Vlbf)
8. INSTALL OIL LEVEL SENSOR
(a) Install a new gasket to the level sensor.
(b) Install the level sensor with the 4 bolts.
Torque: 5.4 NVm (55 kgfVcm, 48 in.Vlbf)
(c) Connect the level sensor connector.
9. INSTALL OIL DIPSTICK GUIDE AND DIPSTICK
(a) Install a new O±ring on the dipstick guide.
(b) Install the guide with the bolt.
10. INSTALL CRANKSHAFT TIMING PULLEY
(See step 1 in timing belt installation in Engine Mechani-
cal)
11. INSTALL IDLER PULLEY
(See step 2 in timing belt installation in Engine Mechani-
cal)
± ENGINELUBRICATION SYSTEMEG±375