2005 TOYOTA AVENSIS catalytic converter

± INTRODUCTIONTERMS
01±43
AVENSIS REPAIR MANUAL (RM1018E) 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±Volatile 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

01±44
± INTRODUCTIONTERMS
AVENSIS REPAIR MANUAL (RM1018E) TCM
Transmission Control ModuleTransmission ECU, ECT ECU
TPThrottle PositionThrottle Position
TRTransmission Range±
TVVThermal Vacuum ValveBimetallic Vacuum Switching Valve (BVSV)
Thermostatic Vacuum Switching Valve (TVSV)
TWCThree±Way Catalytic Converter
Three±Way Catalytic (TWC)
Manifold Converter
CC
RO
TWC+OCThree±Way + Oxidation Catalytic ConverterCCR + CCo
VA FVolume Air FlowAir Flow Meter
VRVoltage RegulatorVoltage Regulator
VSSVehicle Speed SensorVehicle Speed Sensor
WOTWide Open ThrottleFull Throttle
WU±OCWarm Up Oxidation Catalytic Converter±
WU±TWCWarm Up Three±Way Catalytic Converter±
3GRThird Gear±
4GRFourth Gear±

010B9±11
± INTRODUCTIONTERMS
01±37
AVENSIS REPAIR MANUAL (RM1018E)
TERMS
ABBREVIATIONS USED IN THIS MANUAL
AbbreviationsMeaning
ABSAnti±Lock Brake System
A/CAir Conditioner
ACAlternating Current
ACCAccessory
ACISAcoustic Control Induction System
ACSDAutomatic Cold Start Device
A.D.D.Automatic Disconnecting Differential
A/FAir±Fuel Ratio
AHCActive Height Control Suspension
ALRAutomatic Locking Retractor
ALTAlternator
AMPAmplifier
ANTAntenna
Approx.Approximately
ASSYAssembly
A/T, ATMAutomatic Transmission (Transaxle)
AT FAutomatic Transmission Fluid
AUTOAutomatic
AUXAuxiliary
AV GAverage
AV SAdaptive Variable Suspension
B+Battery Voltage
BABrake Assist
BACSBoost Altitude Compensation System
BATBattery
BDCBottom Dead Center
B/LBi±Level
B/SBore±Stroke Ratio
BTDCBefore Top Dead Center
BVSVBimetallic Vacuum Switching Valve
CANController Area Network
CBCircuit Breaker
CCoCatalytic Converter For Oxidation
CDCompact Disc
CFCornering Force
CGCenter Of Gravity
CHChannel
CKDComplete Knock Down
COMB.Combination
CPECoupe
CPSCombustion Pressure Sensor
CPUCentral Processing Unit
CRSChild Restraint System
CTRCenter
C/VCheck Valve
CVControl Valve
CWCurb Weight
DCDirect Current

± INTRODUCTIONTERMS
01±41
AVENSIS REPAIR MANUAL (RM1018E)Abbreviations Meaning
TFTToyota Free±Tronic
TISTotal Information System For Vehicle Development
T/MTransmission
TMCTOYOTA Motor Corporation
TMMKTOYOTA Motor Manufacturing Kentucky, Inc.
TRCTraction Control System
TURBOTurbocharge
TWCThree±Way Catalyst
U/DUnderdrive
U/SUndersize
VCVVacuum Control Valve
VENTVentilator
VINVehicle Identification Number
VPSVariable Power Steering
VSCVehicle Stability Control
VSVVacuum Switching Valve
VTVVacuum Transmitting Valve
VVT±iVariable Valve Timing±intelligent
w/With
WGNWagon
W/HWire Harness
w/oWithout
WU±TWCWarm Up Three±way Catalytic Converter
WU±OCWarm Up Oxidation Catalytic Converter
1stFirst
2ndSecond
2WDTwo Wheel Drive Vehicle (4 x 2)
3rdThird
4thFourth
4WDFour Wheel Drive Vehicle (4 x 4)
4WSFour Wheel Steering System
5thFifth

01±18
± INTRODUCTIONREPAIR INSTRUCTION
AVENSIS REPAIR MANUAL (RM1018E)
NOTICE:

Confirm that the VSC warning light blinks.

VSC system will be reset when the engine is re-
started.

Fasten the vehicle with lock chains.
(b) NOTICES OF RELATED OPERATIONS TO VSC
(1) Do not carry out unnecessary installation and re-
moval as it might disorder the adjustment of related
parts to VSC.
(2) Be sure to carry out the preparation for operation
and the confirmation of operation completion in ac-
cordance with the instruction of the text and when
the related operations to VSC are performed.
10. FOR VEHICLES EQUIPPED WITH CATALYTIC CONVERTER
CAUTION:
If a large amount of unburned gasoline flows into the converter, it may cause overheating and is a
fire hazard. To prevent this, observe the following precautions.
(a) Use only unleaded gasoline.
(b) Avoid prolonged idling.
Avoid idling the engine for more than 20 minutes.
(c) Avoid a spark jump test.
(1) Perform a spark jump test only when absolutely necessary. Perform this test as rapidly as pos-
sible.
(2) While testing, never race the engine.
(d) Avoid a prolonged engine compression measurement.
Engine compression measurements must be performed as rapidly as possible.
(e) Do not run the engine when the fuel tank is nearly empty. This may cause the engine to misfire and
create an extra load on the converter.

±
DIAGNOSTICS SFI SYSTEM (1ZZ±FE/3ZZ±FE)
05±17
AVENSIS REPAIR MANUAL (RM1018E)P0171*
3
(05±67)
System too Lean (Fuel Trim)
(Bank1)


Air induction system

Injector blockage

PCV hose

Mass air flow meter

Engine coolant temperature sensor

Fuel pressure

Open or short in heated oxygen sensor circuit

Heated oxygen sensor

ECM

P0172*3
(05±67)
System too Rich (Fuel Trim)
(Bank1)

Injector leak, blockage

Mass air flow meter

Engine coolant temperature sensor

Ignition system

Fuel pressure

Open or short in heated oxygen sensor circuit

Gas leakage in exhaust system

Heated oxygen sensor

ECM

P0300*3
(05±73)
Random/Multiple Cylinder Misfire
Detected
Open or short in engine wire

Connector connection
Vac m hose connectionP0301*3
(05±73)Cylinder 1 Misfire Detected

Vacuum hose connection

PCV hose

Ignition system
P0302*3
(05±73)Cylinder 2 Misfire Detected

Injector

Fuel pressure

Mass air flow meter

P0303*3
(05±73)Cylinder 3 Misfire Detected

Mass air flow meter

Engine coolant temperature sensor

Compression pressure

Valve clearance
P0304*3
(05±73)Cylinder 4 Misfire Detected

Valve clearance

Valve timing

ECM
P0325
(05±81)Knock Sensor 1 Circuit Malfunc-
tion (Bank 1)
Open or short in knock sensor circuit

Knock sensor (under±torqued or loose)

ECM

P0335
(05±84)Crankshaft Position Sensor ºAº
Circuit Malfunction

Open or short in crankshaft position sensor circuit

Crankshaft position sensor

Crank angle sensor plate

ECM

P0340
(05±88)Camshaft Position Sensor Circuit
Malfunction

Open or short in camshaft position sensor circuit

Camshaft position sensor

Intake camshaft

Timing chain has jumped a tooth

ECM

P0420*3
(05±91)
Catalyst System Efficiency Be-
low Threshold (Bank 1)

Gas leakage in exhaust system

Heated oxygen sensor

Three±way catalytic converter

ECM

P0443
(05±94)Evaporative Emission Control
System Purge Control Vent Cir-
cuit Malfunction
Open or short in VSV for EVAP circuit

VSV for EVAP

ECM

P0500
(05±98)Vehicle Speed Sensor Malfunc-
tion

Open or short in speed sensor circuit

Speed sensor

Combination meter

ECM

Skid control ECU


A66651A±A SectionAir Solid Electrolyte
(Zirconia Element)
Platinum ElectrodeHeater
Exhaust Gas
CoverIdeal Air±Fuel Mixture
Output Voltage
Richer ± Air Fuel Ratio ± Leaner Element
AA
± DIAGNOSTICSSFI SYSTEM (1ZZ±FE/3ZZ±FE)
05±45
AVENSIS REPAIR MANUAL (RM1018E)
DTC P0125 INSUFFICIENT COOLANT TEMP. FOR
CLOSED LOOP FUEL CONTROL
CIRCUIT DESCRIPTION
The heated oxygen sensor is the planar type. Compared to the conventional type, the sensor element and
the heater portions have a narrower overall. The heater can directly conduct its heat to the zirconia element
via the alumina, it helps to accerate the sensor activation.
To obtain a high purification rate for the CO, HC and NOx components of the exhaust gas, a three ± way
catalytic converter is used. For the most efficient use of the three ± way catalytic converter, the air ± fuel ratio
must be precisely controlled so that it is always close to the stoichiometric air ± fuel ratio.
The heated oxygen sensor has the characteristic whereby its output voltage changes suddenly in the vicinity
of the stoichiometric air±fuel ratio. This is used to detect the oxygen concentration in the exhaust gas and
provide the ECM with feedback control the air±fuel ratio.
When the air±fuel ratio becomes LEAN, the oxygen concentration in the exhaust gas increases. And the
heated oxygen sensor informs the ECM of the LEAN condition (low voltage, i. e. less than 0.45 V ).
When the air±fuel ratio is RICHER than the stoichiometric air±fuel ratio, the oxygen concentration in the ex-
haust gas is reduced. And the heated oxygen sensor informs the ECM of the RICH condition (high voltage,
i. e. more than 0.45V). The ECM judges by the voltage output from the heated oxygen sensor whether the
air±fuel ratio is RICH or LEAN and controls the injection time accordingly. If the malfunction of the heated
oxygen sensor causes an output of abnomal voltage, the ECM becomes unable to perform accurate air±fuel
ratio control.
The heated oxygen sensors include a heater which heats the zirconia element. The heater is controlled by
the ECM. When the intake air volume is low (the temperature of the exhaust gas is low), current flows to the
heater in order to heat the sensor for the accurate oxygen concentration detection.
DTC NoDTC Detecting ConditionTrouble Area
P0125
After engine is warmed up, heated oxygen sensor output* does
not change when conditions (a), (b), (c) and (d) continue for at
least 1.5 min:
*: Output value changes at inside of the ECM only
(a) Engine speed: 1,400 rpm or more
(b) Vehicle speed: 40 to 100 km/h (25 to 62 mph)
(c) Throttle valve is not fully closed
(d) 180 sec. or more after starting engine
Open or short in heated oxygen sensor circuit

Heated oxygen sensor

Air induction system

Fuel pressure

Injector

Gas leakage in exhaust system

ECM
05C69±01

A58692
Waveform of heated oxygen
Sensor in front of CatalystNormal CatalystWaveform of Heated Oxygen
Sensor behind Catalyst
A58693
Engine Speed
2,500 ± 3,000 rpm
Idling
IG SW OFF
Warmed up 3 min. Check Time (a)(b)(c) (d)
± DIAGNOSTICSSFI SYSTEM (1ZZ±FE/3ZZ±FE)
05±91
AVENSIS REPAIR MANUAL (RM1018E)
DTC P0420 CATALYST SYSTEM EFFICIENCY BELOW
THRESHOLD (BANK 1)
CIRCUIT DESCRIPTION
The ECM compares the 2 waveforms of the heated oxygen sensors located before and after the catalyst
to determine whether or not the catalyst performance has deteriorated.
Air±fuel ratio feedback compensation keeps the waveform of the heated oxygen sensor in front of the cata-
lyst alternates between back and forth, from rich to lean.
If the catalyst is functioning normally, the waveform of the heated oxygen sensor behind the catalyst switches
back and forth between rich and lean much more slowly than the waveform of the heated oxygen sensor
in front of the catalyst.
When both waveforms change at a similar rate, it indicates that the catalyst performance has deteriorated.
DTC No.DTC Detecting ConditionTrouble Area
P0420
After engine and catalyst are warmed up, and while vehicle is
driven within set vehicle and engine speed range, waveforms
of heated oxygen sensors have same amplitude (2 trip detec-
tion logic)
Gas leakage in exhaust system

Heated oxygen sensor

Three±way catalytic converter

ECM
CONFIRMATION DRIVING PATTERN
05B43±02