1999 TOYOTA CAMRY IAC valve

INTRODUCTIONGLOSSARY OF SAE AND TOYOTA TERMS ±
IN±7
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±Volatile 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±

INTRODUCTIONGLOSSARY OF SAE AND TOYOTA TERMS ±
IN±7
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±Volatile 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±

INTRODUCTIONGLOSSARY OF SAE AND TOYOTA TERMS ±
IN±7
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±Volatile 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±

± DIAGNOSTICSENGINE (5S±FE)
DI±15
250 Author: Date:
(b) TOYOTA Enhanced Signals.
TOYOTA hand±held tester displayMeasurement ItemNormal Condition*1
MISFIRE RPMEngine RPM for first misfire rangeMisfire 0: 0 rpm
MISFIRE LOADEngine load for first misfire rangeMisfire 0: 0 g/r
INJECTORFuel injection time for cylinder No.1Idling: 2.9 ~ 5.1 ms
IAC DUTY RATIOIntake Air Control Valve Duty Ratio
Opening ratio rotary solenoid type IAC valveIdling: 25 ~ 62 %
STARTER SIGStarter SignalCranking: ON
CTP SIGClosed Throttle Position SignalThrottle fully closed: ON
A/C SIGA/C Switch SignalA/C ON: ON
PNP SIGPark/Neutral Position Switch SignalP or N position: ON
ELECTCL LOAD SIGElectrical Load SignalDefogger S/W ON: ON
STOP LIGHT SWStop Light Switch SignalStop light switch ON: ON
PS OIL PRESS SWPower Steering Oil Pressure Switch SignalTurn steering wheel: ON
FC IDLFuel Cut Idle: Fuel cut when throttle valve fully
closed, during decelerationFuel cut operating: ON
FC TAUFuel Cut TAU: Fuel cut during very light loadFuel cut operating: ON
CYL#1, CYL#2, CYL#3, CYL#4Abnormal revolution variation for each cylinder0 %
IGNITIONTotal number of ignition for every 1,000 revolu-
tions0 ~ 2,000 rpm
EGR SYSTEMEGR system operating conditionIdling: OFF
FUEL PUMPFuel Pump SignalIdling: ON
A/C CUT SIGA/C Cut SignalA/C S/W OFF: ON
A/C MAG CLUTCHA/C Switch SignalA/C ON: ON
EVAP (PURGE) VSVEVAP VSV SignalVSV operating: Avove 30 %
VAPOR PRESS VSVVapor Pressure VSV SignalVSV operating: ON
TOTAL FT B1Total Fuel Trim Bank 1: Average value for fuel
trim system of bank 1Idling: 0.8 ~ 1.2 V
O2 LR B1, S1 *2
Heated Oxygen Sensor Lean Rich Bank 1 Sen-
sor 1: Response time for oxygen sensor output to
switch from lean to rich
Idling after warming up: 0 ~ 1,000 msec.
O2 RL B1, S1 *2
Heated Oxygen Sensor Rich Lean Bank 1 Sen-
sor 1: Response time for oxygen sensor output to
switch from rich to lean
Idling after warming up: 0 ~ 1,000 msec.
*1: If no conditions are specifically stated for ºldlingº, it means the shift lever is at N or P position, the A/C
switch is OFF and all accessory switches are OFF.
*2: Except California Specification vehicles.

± DIAGNOSTICSENGINE (5S±FE)
DI±19
254 Author: Date:
DTC No.
(See Page)Detection ItemTrouble AreaMIL*1Memory
P0500
(DI±145)Vehicle Speed Sensor
Malfunction
Combination meter
Open or short in No.1 vehicle speed sensor circuit
No.1 vehicle speed sensor
ECM

P0505
(DI±148)Idle Control System
Malfunction
IAC valve is stuck or closed
Open or short in IAC valve circuit
Open or short in A/C switch circuit
Air intake (hose loose)
ECM

*1: 


MIL lights up
2. MANUFACTURER CONTROLLED
DTC No.
(See Page)Detection ItemTrouble AreaMIL*1Memory
*2
P1130
(DI±152)A/F Sensor Circuit
Range/Performance MalfunctionOpen or short in A/F sensor circuit
A/F sensor
ECM

*2
P1133
(DI±157)A/F Sensor Circuit Response
MalfunctionA/F sensor
*2
P1135
(DI±161)A/F Sensor Heater Circuit
MalfunctionOpen or short in heater circuit of A/F sensor
A/F sensor heater
ECM

P1300
(DI±163)Igniter Circuit Malfunction (No.1)
Open or short in IGF or IGT circuit from igniter to ECM
Ignition coil (No.1)
ECM

P1310
(DI±163)Igniter Circuit Malfunction (No.2)
Open or short in IGF or IGT circuit from igniter to ECM
Ignition coil (No.2)
ECM

P1335
(DI±169)Crankshaft Position Sensor Cir-
cuit Malfunction
(During engine running)Open short in crankshaft position sensor circuit
Crankshaft position sensor
ECM
±
*3
P1520
(DI±170)Stop Light Switch Signal Mal-
functionShort in stop light switch signal circuit
Stop light switch
ECM

P1600
(DI±173)ECM BATT MalfunctionOpen in back up power source circuit
ECM
*3
P1780
(DI±175)Park/Neutral Position Switch
MalfunctionShort in park/neutral position switch circuit
Park/neutral position switch
ECM

*1: 


MIL lights up
*
2: Only for California Specification vehicles
*
3: Only for A/T models

P01559
Throttle Valve
To Cylinder ECM Signal From
Air
Cleaner
Valve
IAC Valve
Intake Air
Chamber
A07553
B±Y 9
2B±Y B±Y
II3J19
J/CIAC ValveECM
1
3 2
B
EFI
5
1 Engine Room J/B No.2
42
2J
W±B
B
ISCO
E01
E01 ISCC10
9W
B±OE9
E9
1
2A
2K
EFI Relay
EB
From
BatteryB
*1: w/o Immobiliser
*2: w/ Immobiliser(*1) (*2)
E97
E96
(*2) (*1)
E107MREL2FB±W B±W
II4
(*2)
7
6(*2) (*2)
3
B±R
(*1)From
Ignition SW DI±148
± DIAGNOSTICSENGINE (5S±FE)
383 Author: Date:
DTC P0505 Idle Control System Malfunction
CIRCUIT DESCRIPTION
The rotary solenoid type IAC valve is located on the throttle
body and intake air bypassing the throttle valve is directed to
the IAC valve through a passage.
In this way the intake air volume bypassing the throttle valve is
regulated, controlling the engine speed.
The ECM operates only the IAC valve to perform idle±up and
provide feedback for the target idling speed.
DTC No.DTC Detecting ConditionTrouble AreaTrouble Area
P0505Idle speed continues to vary greatly from the target speed
(2 trip detection logic)

IAC valve is stuck or closed

Open or short in IAC valve circuit

Open or short in A/C switch circuit

Air intake (hose loose)

ECM
WIRING DIAGRAM
DI01C±05

A00416
A03022A03426
E9 Connector
RSC(+) RSO(+)
E9 Connector
RSO(+)
RSC(+) w/o Immobiliser
w/ Immobiliser
DI±150
± DIAGNOSTICSENGINE (5S±FE)
385 Author: Date:
2 Check voltage between terminals RSO, RSC of ECM connector and body ground.
PREPARATION:
(a) Remove the glove compartment (See page SF±64).
(b) Disconnect the E9 connector of the ECM.
(c) Turn the ignition switch ON.
CHECK:
Measure voltage between terminals RSO, RSC of the ECM
connector and body ground,
OK:
Voltage: 9 ~ 14 V
OK Go to step 4.
NG
3 Check IAC valve (See page SF±35).
NG Replace IAC valve.
OK
Check for open and short in harness and connector between engine room J/B No.2 and IAC valve,
and IAC valve and ECM (See page IN±31).

± DIAGNOSTICSENGINE (5S±FE)
DI±151
386 Author: Date:
4 Check operation of IAC valve (See page SF±35).
NG Repair or replace IAC valve.
OK
5 Check blockage of IAC valve and passage to bypass throttle valve.
NG Repair or replace IAC valve.
OK
Check and replace ECM (See page IN±31).
6 Check for A/C signal circuit (See page AC±84).
NG Repair or replace.
OK
Check air induction system
(See page SF±1).