Page 83 of 1807
IN-36
- INTRODUCTIONTERMS
36 Author: Date:
1997 SUPRA (RM502U) HO2S
Heated Oxygen SensorHeated Oxygen Sensor (HO2S)
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
Page 560 of 1807
DI4SF-01
Vehicle Brought to Workshop
Customer Problem Analysis P. DI-146
Problem Symptom Confirmation
If the engine does not start, perform steps 10 and 12 firstConnect the OBD II scan tool or TOYOTA hand-held tester to DLC3 P. DI-147
If the display indicates a communication fault in the tool, inspect DLC3 P. DI-147
Check DTC and Freezed Frame Data (Precheck)
Record or Print DTC and Freezed Frame Data P. DI-147
Clear DTC and Freezed Frame Data P. DI-147
Visual Inspection
Setting the Check Mode Diagnosis P. DI-147
Symptom Simulation P. IN-18
DTC Chart P. DI-158
Matrix Chart of Problem Symptoms P. DI-169
Circuit Inspection P. DI-170
Adjustment, Repair
DTC Check P. DI-14
Titles insideare titles of pages in
in the bottom portion. See the indicated
pages for detailed explanations.this manual, with the page number indicated
Malfunction
occurs.Malfunction does not occur.
Parts Inspection
Check for Intermittent Problems P. DI-147
Identification of Problem
Confirmation Test
End 1
2
3
4
5
6
7
108
9
11
12
13
15 14
16
Normal Malfunction code.
17Basic Inspection P. DI-147
- DIAGNOSTICSENGINE (2JZ-GTE)
DI-145
373 Author: Date:
1997 SUPRA (RM502U)
ENGINE (2JZ-GTE)
HOW TO PROCEED WITH TROUBLESHOOTING
Troubleshoot in accordance with the produce on the following page.
Page 599 of 1807
FI6480
Throttle Position
SensorECM
VCC
VTA1
IDL1
E25V
B+ DI-184
- DIAGNOSTICSENGINE (2JZ-GTE)
412 Author: Date:
1997 SUPRA (RM502U)
DTC P0120 Throttle/Pedal Position Sensor/Switch ºAº
Circuit Malfunction
CIRCUIT DESCRIPTION
The throttle position sensor is mounted in the throttle body and
detects the throttle valve opening angle. When the throttle valve
is fully closed, the IDL1 contacts in the throttle position sensor
are on, so the voltage at the terminal IDL1 of the ECM becomes
0 V. At this time, a voltage of approximately 0.7 V is applied to
terminal VTA1 of the ECM. When the throttle valve is opened,
the IDL1 contacts go off and thus the power source voltage of
approximately 12 V in the ECM is applied to the terminal IDL1
of the ECM. The voltage applied to the terminal VTA1 of the
ECM increases in proportion to the opening angle of the throttle
valve and becomes approximately 3.2 - 4.9 V when the throttle
valve is fully opened. The ECM judges the vehicle driving condi-
tions from these signals input from terminals VTA1 and IDL1,
and uses them as one of the conditions for deciding the air-fuel
ratio correction, power increases correction and fuel-cut con-
trol etc.
DTC No.DTC Detecting ConditionTrouble Area
P0120
Condition (a) or (b) conditions:
(a) VTA < 0.25 V, and closed throttle position switch is OFF
(b) VTA > 4.9 VOpen or short in throttle position sensor circuit
Throttle position sensor
ECM
HINT:
If there is open circuit in IDL line, DTC P0120 does not indicate.
After confirming DTC P0120 use the OBD II scan tool or TOYOTA hand-held tester to confirm the
throttle valve opening percentage and closed throttle position switch condition.
Throttle valve opening position expressed as percentageTblAThrottle valve fully closedThrottle valve fully openTrouble Area
0 %0 %VC line open
VTA1 line open or short
Approx. 100 %Approx. 100 %E2 line open
DI4SR-01