1996 TOYOTA TERCEL OBD port

- INTRODUCTIONTERMS
IN-37
1996 TERCEL (RM440U) 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 (IDL)
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 Lamp
MSTManifold Surface Temperature-
MVZManifold Vacuum Zone-
NVRAMNon-V olatile Random Access Memory-
O2SOxygen SensorOxygen Sensor, O2 Sensor (O2S)
OBDOn-Board DiagnosticOn-Board Diagnostic System (OBD)
OCOxidation Catalytic ConverterOxidation Catalyst Convert (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 BypassE-ABV
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

DI4LC-02
Vehicle Brought to Workshop
Customer Problem Analysis
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-3
If the display indicates a communication fault in the tool, inspect DLC3 P. DI-3
Check DTC and Freeze Frame Data (Pre-check)
Record or Print DTC and Freeze Frame Data P. DI-3
Clear DTC and Freeze Frame Data P. DI-3
Visual Inspection
Setting the Check Mode Diagnosis P. DI-3
Symptom Simulation P. IN-16
Basic Inspection P. DI-3DTC Chart P. DI-13
Matrix Chart of Problem Symptom P. DI-19
Circuit Inspection P. DI-20
Adjustment, Repair
DTC Check P. DI-3
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-3
Identification of Problem
Confirmation Test
End 1
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3
4
5
6
7
108
9
11
12
13
15 14
16
Normal Malfunction code.
17
P. DI-2
- DIAGNOSTICSENGINE
DI-1
175 Author
: Date
:
1996 TERCEL (RM440U)
ENGINE
HOW TO PROCEED WITH TROUBLESHOOTING
Troubleshoot in accordance with the procedure on the following pages.

DI1E3-06
P01242
750
450
100 (3.96)
3.6
1.2
(840) 2.4
150
60 20
(112)kPa mmHg
Manifold Absolute Pressure
Output Voltage
V DI-20
- DIAGNOSTICSENGINE
1996 TERCEL (RM440U)
CIRCUIT INSPECTION
DTC P0105 Manifold Absolute Pressure/Barometric
Pressure Circuit Malfunction
CIRCUIT DESCRIPTION
By a built-in sensor unit, the manifold absolute pressure sensor
detects the intake manifold pressure as a voltage. The ECM
then determines the basic injection duration and basic injection
advance angle based on this voltage. Since the manifold abso-
lute pressure sensor does not use the atmospheric pressure as
a criterion, but senses the absolute pressure inside the intake
manifold (the pressure in proportion to the present absolute
vacuum 0), it is not influenced by fluctuations in the atmospheric
pressure due to high altitude and other factors. This permits it
to control the air-fuel ratio at the proper lever under all condi-
tions.
DTC No.DTC Detection ConditionTrouble Area
P0105Open or short manifold absolute pressure sensor circuit

Open or short in manifold absolute pressure sensor circuit

Manifold absolute pressure sensor

ECM
If the ECM detects DTC P0105, it operates the fail-safe function, keeping the ignition timing and injection
volume constant and making it possible to drive the vehicle.
HINT:
After confirming DTC P0105, use the OBDII scan tool or TOYOTA hand-held tester to confirm the manifold
absolute pressure from the CURRENT DATA.
Manifold absolute pressureTrouble Area
0 kPaPIM circuit short
130 kPa or more
VC circuit open or short
PIM circuit open
E2 circuit open

P24296
Throttle Position
Sensor
E2 VTAECM
VC
- DIAGNOSTICSENGINE
DI-33
1996 TERCEL (RM440U)
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, a voltage of approximately 0.3 - 0.8 V is applied
to terminal VTA of the ECM. The voltage applied to the terminal
VTA 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 ve-
hicle driving conditions from these signals input from terminal
VTA and uses them as one of the conditions for deciding the
air-fuel ratio correction, power increases correction and fuel-
cut control etc.
DTC No.DTC Detection ConditionTrouble Area
P0120
Condition (a) or (b) continues:
(a) VTA < 0.1 V
(b) VTA > 4.9 V
Open or short in throttle position sensor circuit

Throttle position sensor

ECM
HINT:
After confirming DTC P0120, use the OBD II scan tool or TOYOTA hand-held tester to confirm the throttle
valve opening percentage.
Throttle valve opening position expressed as percentageTblAThrottle valve fully closedThrottle valve fully openTrouble Area
0 %0 %VC line open
VTA line open or short
100 %100 %E2 line open
DI1E8-08