1995 TOYOTA SUPRA relay

 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

FUEL PUMP
ON±VEHICLE INSPECTION
1. CHECK FUEL PUMP OPERATION
(a) Using SST, connect terminals +B and FP of the DLC 1.
SST 09843±18020
(b) Turn the ignition switch ON.
NOTICE: Do not start the engine.
(c) Check that there is pressure in the fuel inlet hose from the fuel
filter.
HINT: If there is fuel pressure, you will hear the sound of fuel
flowing.
If there is no pressure, check the following parts:
wFuse
wEFI main relay
wFuel pump
wECM
wWiring connections
(d) Turn the ignition switch OFF.
(e) Remove the SST from the DLC1.
SST 09843±18020
2. CHECK FUEL PRESSURE
(a) Check the battery voltage is above 12 V.
(b) Disconnect the negative (±) terminals cable from the battery.
(c) Remove the 2 nuts, and disconnect the No.2 vacuum pipe
from the air intake chamber and intake manifold.
(d) Remove the union bolt and 2 gaskets, disconnect the fuel
inlet pipe from the delivery pipe.
CAUTION:

Put a shop towel under the delivery pipe.

Slowly loosen the union bolt.
(e) Install the fuel inlet pipe and SST (pressure gauge) to the
delivery pipe with the 3 gaskets and SST (union bolt).
SST 09268±45012
Torque: 42 NVm (420 kgfVcm, 30 ftVlbf)
(f) Wipe off any splattered gasoline.
(g) Using SST, connect terminals +B and FP of the DLC 1.
SST 09843±18020
± ENGINESFI SYSTEM (2JZ±GE)EG±193

EFI MAIN RELAY
EFI MAIN RELAY INSPECTION
1. REMOVE EFI MAIN RELAY
LOCATION: In the engine compartment relay box.
2. INSPECT EFI MAIN RELAY
A. Inspect relay continuity
(a) Using an ohmmeter, check that there is continuity between
terminals 1 and 2.
(b) Check that there is no continuity between terminals 3 and 5.
If continuity is not as specified, replace the relay.
B. Inspect relay operation
(a) Apply battery voltage across terminals 1 and 2.
(b) Using an ohmmeter, check that there is continuity between
terminals 3 and 5.
If operation is not as specified, replace the relay.
3. REINSTALL EFI MAIN RELAY
± ENGINESFI SYSTEM (2JZ±GE)EG±235

FUEL PUMP
ON±VEHICLE INSPECTION
1. CHECK FUEL PUMP OPERATION
(a) Using SST, connect terminals +B and FP of the DLC 1.
SST 09843±18020
(b) Turn the ignition switch ON.
NOTICE: Do not start the engine.
(c) Check that there is pressure in the fuel inlet hose from the fuel
filter.
HINT: If there is fuel pressure, you will hear the sound of fuel
flowing.
If there is no pressure, check the following parts:
wFuses
wEFI No.2 relay
wFuel pump
wECM
wWiring connections
(d) Turn the ignition switch OFF
(e) Remove the SST from the DLC1.
SST 09843±18020
2. CHECK FUEL PRESSURE
(a) Check the battery voltage is above 12 V.
(b) Disconnect the negative (±) terminal cable from the battery.
(c) Remove the union bolt and 2 gaskets, disconnect the fuel
inlet hose from the fuel filter.
CAUTION:
wPut a suitable container or shop towel under the fuel filter.
wSlowly loosen the union bolt.
(d) Install the fuel inlet hose and SST (pressure gauge) to the
fuel filter with the 3 gaskets and SST (union bolt).
SST 09268±45012
Torque: 29 NVm (300 kgfVcm, 22 ftVlbf)
(e) Wipe off any splattered gasoline.
(f) Using SST, connect terminals +B and FP of the DLC 1.
SST 09843±18020 EG±264
± ENGINESFI SYSTEM (2JZ±GTE)

IAC VALVE INSTALLATION
1. INSTALL IAC VALVE
(a) Install the check valve and seal washer.
NOTICE: Be careful of the check valve and seal washer instal-
lation direction.
(b) Connect these hoses:
wAir hose
wWater bypass hose (from No.2 water bypass pipe)
wWater bypass hose (from No.4 water bypass pipe)
(c) Install a new gasket and the IAC valve with the 2 bolts.
Torque: 21 NVm (210 kgfVcm, 15 ftVlbf)
2. CONNECT IAC VALVE CONNECTOR
3. FILL WITH ENGINE COOLANT
EFI MAIN RELAY
EFI MAIN RELAY INSPECTION
1. REMOVE EFI MAIN RELAY
LOCATION: In the engine compartment relay box.
2. INSPECT EFI MAIN RELAY
A. Inspect relay continuity
(a) Using an ohmmeter, check that there is continuity between
terminals 1 and 2.
(b) Check that there is no continuity between terminals 3 and 5.
If continuity is not as specified, replace the relay.
B. Inspect relay operation
(a) Apply battery voltage across terminals 1 and 2.
(b) Using an ohmmeter, check that there is continuity between
terminals 3 and 5.
If operation is not as specified, replace the relay.
3. REINSTALL EFI MAIN RELAY EG±298
± ENGINESFI SYSTEM (2JZ±GTE)

EFI NO.2 RELAY
EFI NO.2 RELAY INSPECTION
1. REMOVE EFI NO.2 RELAY
LOCATION: In the engine compartment relay box.
2. INSPECT EFI NO.2 RELAY
A. Inspect relay continuity
(a) Using an ohmmeter, check that there is continuity between
terminals 1 and 2.
(b) Check that there is no continuity between terminals 3 and 5.
If continuity is not as specified, replace the relay.
B. Inspect relay operation
(a) Apply battery voltage across terminals 1 and 2.
(b) Using an ohmmeter, check that there is continuity between
terminals 3 and 5.
If operation is not as specified, replace the relay.
3. REINSTALL EFI NO.2 RELAY
± ENGINESFI SYSTEM (2JZ±GTE)EG±299

STARTER RELAY
STARTER RELAY INSPECTION
1. REMOVE STARTER RELAY (ºSTº)
LOCATION: In the engine compartment relay box.
Remove the relay box cover and starter relay.
2. INSPECT STARTER RELAY
A. Inspect relay continuity
(a) Using an ohmmeter, check that there is continuity between
terminals 1 and 2.
(b) Check that there is no continuity between terminals 3 and 5.
If continuity is not as specified, replace the relay.
B. Inspect relay operation
(a) Apply battery voltage across terminals 1 and 2.
(b) Using an ohmmeter, check that there is continuity between
terminals 2 and 5.
If operation is not as specified, replace the relay.
3. REINSTALL STARTER RELAY ST±12
± STARTING SYSTEMSTARTER RELAY

 
 
 Trouble Area
 
 
 
Malfunction
Indicator
Lamp*
1
 
 
 Memory*2
 
 
 See page
 
 
Trouble Area
 
 
Normal
Mode 
 
Test
Mode 
 
Memory
 
 
See page
 
 
 
 

Open or short in volume air flow meter circuit

Volume air flow meter

ECM
 
 
 
 
ON
 
 
 
 
N.A.
 
 
 
 

 
 
 
 
EG±438
 
 
 

ECM
 
 
 
ON
 
 
 
ON
 
 
 

 
 
 
EG±441
 
 
 
 

Open or short in throttle position sensor circuit

Throttle position sensor

ECM
 
 
 
 
ON
 
 
 
 
ON
 
 
 
 

 
 
 
 
EG±442
 
 
 
 
 
 
 
 
 

No.1 vehicle speed sensor

Telltale light RH

Open or short in No.1 vehicle speed sensor circuit

ECM
 
 
 
 
 
 
 
 
 
OFF
 
 
 
 
 
 
 
 
 
OFF
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
EG±445
 
 
 

Open or short in starter signal circuit

Open or short in ignition switch or starter relay circuit

ECM
 
 
 N.A.
 
 
 OFF
 
 
 X
 
 
 EG±448
 
 
 
 
 

Open or short in No.1 knock sensor circuit

No.1 knock sensor (looseness)

ECM
 
 
 
 
 
ON
 
 
 
 
 
N.A.
 
 
 
 
 

 
 
 
 
 
EG±450
 
 
 
 

ECM
 
 
 
 
ON
 
 
 
 
N.A.
 
 
 
 
X
 
 
 
 
EG±450
 
 
 
 
 

Open or short in No.2 knock sensor circuit

No.2 knock sensor (looseness)

ECM
 
 
 
 
 
ON
 
 
 
 
 
N.A.
 
 
 
 
 

 
 
 
 
 
EG±450
*1, 2: See page EG±396.
± ENGINE2JZ±GE ENGINE TROUBLESHOOTINGEG±395