o2 sensor TOYOTA HIGHLANDER 2001 Service Repair Manual

05-200
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
390 Author
: Date
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
OBD II MONITOR SPECIFICATIONS (Key-off Monitor)
Monitor Strategy
Required Sensors/ComponentsPurge VSV and pump module
Frequency of OperationOnce per driving cycle
DurationWithin 15 minutes (varies with fuel in tank)
MIL Operation2 driving cycles
Sequence of OperationNone
Typical Enabling Conditions
The monitor will run whenever these DTCs are not presentSee page 05-16
EVAP key-off monitor runs when all of the following condi-
tions met-
Atmospheric pressure525 to 825 mmHg (70 to 110 kPa)
Battery voltage10.5 V or more
Vehicle speedBelow 4 km/h (2.5 mph)
Ignition switchOFF
Engine conditionNot running
Time after engine stopped5 hours
FTP sensor malfunction (P0450, P0452, P0453)Not detected
Purge VSVNot operated by scan tool
Vent valveNot operated by scan tool
Leak detection pumpNot operated by scan tool
Both of the following conditions are met before IG switch
OFF:Condition 1 and 2
1. Duration that vehicle is driven5 min. or more
2. Purge flowExecuted
ECT4.4 to 35C (40 to 95F)
IAT4.4 to 35C (40 to 95F)
Example of re-start time
First time7 hours
Second time9 hours and 30 min.
Key-of f monitor sequence: 1 to 8
1. Atmospheric pressure
Next sequence is run if following condition met-
Atmospheric pressure change for 10 sec.Within 2.25 mmHg (0.3 kPa) for 1 sec.
2. First reference pressure
Next sequence is run if all of following conditions metCondition 1, 2 and 3
1. FTP when 4 sec. after reference pressure measurement-7.5 mmHg (-1 kPa) or less
2. Reference pressure-36.47 to -7.93 mmHg (-4.85 to -1.057 kPa)
3. Reference pressureSaturated
3. Vent valve stuck closed check
Next sequence is run if following condition met-
FTP change for 10 sec. after vent valve ON (closed)2.25 mmHg (0.3 kPa) or more
4. Vacuum introduction and leak
Next sequence is run if both of following conditions metCondition 1 and 2
1. Vacuum introduction timeWithin 15 min.
2. FTPFTP was saturated
5. Purge VSV stuck closed check
Next sequence is run if following condition met-
FTP change for 10 sec. after purge VSV ON (open)2.25 mmHg (0.3 kPa) or more

- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
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391 Author
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
6. Second reference pressure measurement
Next sequence is run if all of following conditions metCondition 1, 2, 3 and 4
1. FTP when 4 sec. after reference pressure measurement-7.5 mmHg (-1 kPa) or less
2. Reference pressure-36.47 to -7.93 mmHg (-4.85 to -1.057 kPa)
3. Reference pressureSaturated
4. Reference pressure difference between first and secondLess than 5.25 mmHg (0.7 kPa)
7. Leak check
Next sequence is run if following condition met-
FTP when vacuum introduction was completeLower than second reference pressure
8. Atmospheric pressure
Monitor is complete if following-
Atmospheric pressure difference between sequence 1 and 8Within 2.25 mmHg (0.3 kPa)
Typical Malfunction Thresholds
Purge VSV stuck open
FTP when vacuum introduction was completeHigher than reference pressure x 0.2
Purge VSV stuck closed
FTP change for 10 seconds after purge VSV ON (open)Less than 2.25 mmHg (0.3 kPa)
OBD II MONITOR SPECIFICATIONS (Purge Flow Monitor)
Monitor Strategy
Required Sensors/ComponentsPurge VSV and pump module
Frequency of OperationOnce per driving cycle
DurationWithin 30 seconds
MIL Operation2 driving cycles
Sequence OperationNone
Typical Enabling Conditions
The monitor will run whenever these DTCs are not presentSee page 05-16
EngineRunning
ECT4.4C (40F) or more
IAT4.4C (40F) or more
FTP sensor malfunctionNot detected
Purge VSVNot operated by scan tool
EVAP system checkNot operated by scan tool
Battery voltage10 V or more
Purge duty cycle8 % or more
Typical Malfunction Thresholds
Both of the following conditions are met:Condition 1 or 2
1. FTP change when purge operation is startedLess than 0.75 mmHg (0.1 kPa)
2. FTP change during purge operation when vent valve is
closedLess than 3.75 mmHg (0.5 kPa)
MONITOR RESULT (MODE 06)
Refer to page 05-317 for detailed information on Monitor Result.

- DIAGNOSTICSSFI SYSTEM (3MZ-FE)
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
DTC P0442 EVAPORATIVE EMISSION CONTROL
SYSTEM LEAK DETECTED (SMALL LEAK)
DTC P0455 EVAPORATIVE EMISSION CONTROL
SYSTEM LEAK DETECTED (GROSS LEAK)
DTC P0456 EVAPORATIVE EMISSION CONTROL
SYSTEM LEAK DETECTED (VERY SMALL
LEAK)
CIRCUIT DESCRIPTION
The circuit description can be found in the EVAP INSPECTION PROCEDURE (see page 05-679).
INSPECTION PROCEDURE
Refer to the EVAP INSPECTION PROCEDURE (see page 05-679).
MONITOR DESCRIPTION
The ECM tests the Evaporative Emissions (EVAP) system using the fuel tank pressure sensor, Canister
Close Valve (CCV), and EVAP VSV. The ECM closes the EVAP system and creates negative pressure (vacu-
um) into it. The ECM then monitors the internal pressure using the fuel tank pressure sensor (refer to the
Leak Check graphic).
P0442, P0455 and P0456
A leak in the evaporative emission system prompts the ECM to set DTC P0442, P0455 or P0456.
The ECM checks if the EVAP has leaks. First, the ECM opens the EVAP VSV while the CCV is closed. After
a sufficient amount of time has passed, a high negative pressure(vacuum) will develop in the fuel tank as
air is drawn into the intake manifold. The EVAP VSV is then closed. The ECM then monitors the pressure
increase (loss of vacuum) in the fuel tank. If the pressure rises beyond a specified amount, the ECM deter-
mines that the system has a leak, turns on the MIL and outputs a DTC.
The ECM has separate DTCs for small and large leaks:
(1) DTC P0442 is set when the internal fuel tank pressure has a large increase and the EVAP system
has a small leak.
(2) DTC P0455 is set when the EVAP system has a very large leak. The ECM tries to create negative
pressure (vacuum) in the fuel tank by opening the EVAP VSV while the CCV is closed. However,
the fuel tank pressure does not decrease beyond a specified threshold.
(3) DTC P0456 is set when the internal fuel tank pressure increases slightly and the EVAP system
has a very small leak.
05MOQ-01

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2005 HIGHLANDER REPAIR MANUAL (RM1144U)DTC No.
DTC Detection ConditionTrouble Area
P0442
P0455
P0456
Cold engine start.
EVAP VSV has been operated and turned OFF, sealing nega-
tive pressure (vacuum) in system.
ECM begins to monitor fuel tank pressure increase and one
of the following occurs (2 trip detection logic):
(a) Rapid, sharp increase in pressure occurs, indicating small
leak in EVAP system. DTC P0442 is set.
(b) Negative pressure (vacuum) is not strong enough, indicat-
ing large hole in EVAP system. DTC P0455 is set.
(c) Increase in pressure above expected amount occurs, indi-
cating small leak in EVAP system. DTC P0456 is set.
Vacuum hose has cracks, holes, or is blocked, damaged or
disconnected
Fuel tank cap incorrectly installed
Fuel tank cap has cracks or is damaged
Open or short in vapor pressure sensor circuit
Vapor pressure sensor
Open or short in EVAP VSV circuit
EVAP VSV
Open or short in CCV circuit
 CCV
Fuel tank has cracks, holes, or is damaged
Charcoal canister has cracks, holes, or is damaged
Fuel tank over fill check valve cracks, or is damaged
ECM

A76973
ECM
Fuel Tank
Charcoal
Canister EVAP VSV
Vapor Pressure
Sensor
CCV EVAP Service
PortIntake Air
Throttle
Valve
Fuel Tank Cap
Air Cleaner Case
Charcoal Canister Filter Charcoal Filter
Intake Manifold
Purge Line
Air Inlet Line EVAP Line Purge Line
Diaphragm
(Atmospheric Pressure)
Restrictor
Passage
When EVAP VSV is opened, partial vacuum is created
When CCV is
opened, air is
drawn or released
Leak Detection Area
(Purge Valve)
Air Cleaner Filter
- DIAGNOSTICSSFI SYSTEM (3MZ-FE)
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755 Author
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)

05-568
- DIAGNOSTICSSFI SYSTEM (3MZ-FE)
758 Author
: Date
:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
MONITOR STRATEGY
Related DTCs
P0442: EVAP 0.04 inch leak
P0455: EVAP gross leak
P0456: EVAP 0.02 inch leak
Required sensors / components (Main)CCV, EVAP canister, EVAP hose, Fuel cap, Fuel tank and Purge VSV
Required sensors / components (Related)ECT sensor, FTP sensor, IAT sensor, MAF meter, Vehicle speed sensor
Frequency of operationOnce per driving cycle
DurationWithin 90 seconds
MIL operation2 driving cycles
Sequence operationNone
TYPICAL ENABLING CONDITIONS
All:
The monitor will run whenever these DTCs are not presentSee page 05-377
AltitudeLess than 7,870 ft. (2,400 m)
Battery voltage11 V or more
Throttle position learningCompleted
IAT at engine start - ECT at engine start-7 to 11.1C (-12.6 to 20F)
EVAP VSV and CCVNot operated test by scan tool
Either of the following conditions is metCondition 1 or 2
1. Purge duty cycle8% or more (vary with MAF)
2. Purge concentration for 30 seconds-5 %/% or more when vehicle speed is less than 10 km/h (6.25 mph)
RefuelNot refueled with engine running
FTP12.75 mmHg (-1.7 kPa) or more
EVAP 0.02 inch leak P0456:
ECT at engine start4.4 to 32C (39.9 to 89.6F)
IAT at engine start4.4 to 32C (39.9 to 89.6F)
IAT4.4C (39.9F) or more
Vehicle speed changeVehicle is driven by steady speed
Fuel sloshNo sloshing (i.e. fairly smooth road)
Time after engine startWithin 50 minutes
FTP change before vacuum introductionMinimum change
Fuel levelLess than 90 %
0.04 inch leakNot detected
CCV malfunctionNot detected
Vehicle speedLess than 81.25 mph (130 km/h)
Purge VSV malfunctionNot detected
Others:
ECT at engine start4.4 to 35C (39.9 to 95F)
IAT at engine start4.4 to 35C (39.9 to 95F)
IAT4.4C (39.9F) or more
Vehicle speed changeVehicle is driven by steady speed
Fuel sloshNo sloshing (i.e. fairly smooth road)
Time after engine startWithin 50 minutes
FTP change before vacuum introductionMinimum change
Fuel levelLess than 90 %

05-570
- DIAGNOSTICSSFI SYSTEM (3MZ-FE)
760 Author
: Date
:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
DTC P0446 EVAPORATIVE EMISSION CONTROL
SYSTEM VENT CONTROL CIRCUIT
CIRCUIT DESCRIPTION
The circuit description can be found in the EVAP INSPECTION PROCEDURE (see page 05-679).
INSPECTION PROCEDURE
Refer to the EVAP INSPECTION PROCEDURE (see page 05-679).
MONITOR DESCRIPTION
The ECM tests the Evaporative Emissions (EVAP) system using the fuel tank pressure sensor, Canister
Close Valve (CCV), and EVAP VSV. The ECM closes the EVAP system and creates negative pressure (vacu-
um) into it. The ECM then monitors the internal pressure using the fuel tank pressure sensor (refer to the
graphic on page 05-557).
P0446 (FOR SYSTEM DIAGRAM AND DTC DETECTION TIMING CHART, REFER TO DTC P0441
(see page 05-557))
The CCV is open under normal conditions. The CCV has the following features:
(1) After the EVAP VSV purges the EVAP from the fuel tank into the intake manifold, the CCV draws
fumes from the fuel tank into the charcoal canister.
(2) Relieves pressure inside the fuel tank when the pressure has suddenly risen.
(3) Along with the EVAP VSV, creates negative pressure (vacuum) inside the fuel tank and performs
leak tests.
The ECM checks if the CCV is ºstuck closedº. The ECM commands the CCV to open while the EVAP VSV
is open. If high negative pressure (vacuum) develops in the fuel tank and stays for more than 4 seconds,
the ECM determines that the CCV remains closed despite the open command. The ECM would then turn
on the MIL and output a DTC. The engine coolant temperature is not related to the output of this DTC.
The ECM also has a method for checking if the CCV is ºstuck openº. The ECM commands the CCV to close
while the EVAP VSV is open. If a sufficient amount of negative pressure dose not develop in the fuel tank,
the ECM determines that the CCV remains open despite the close command. The ECM would then turn on
the MIL and output a DTC.
DTC No.DTC Detection ConditionTrouble Area
P0446Open or close malfunction in CCV (2 trip detection logic)

Vacuum hose has cracks, holes, or is blocked, damaged or
disconnected

Fuel tank cap incorrectly installed

Fuel tank cap has cracks or is damaged

Open or short in vapor pressure sensor circuit

Vapor pressure sensor

Open or short in EVAP VSV circuit

EVAP VSV

Open or short in CCV circuit

CCV

Fuel tank has cracks, holes, or is damaged

Charcoal canister has cracks, holes, or is damaged

Fuel tank over fill check valve cracks, or is damaged

ECM
05MOR-01

- DIAGNOSTICSSFI SYSTEM (3MZ-FE)
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
MONITOR STRATEGY
Related DTCsP0446: CCV stuck open
P0446: CCV stuck close
Required sensors / components (Main)CCV, EVAP canister, EVAP hose, Fuel cap, Fuel tank and Purge VSV
Required sensors / components (Related)ECT sensor, FTP sensor, IAT sensor, MAF meter, Vehicle speed sensor
Frequency of operationOnce per driving cycle
DurationWithin 60 seconds
MIL operation2 driving cycles
Sequence operationNone
TYPICAL ENABLING CONDITIONS
The monitor will run whenever these DTCs are not presentSee page 05-377
AltitudeLess than 7,870 ft. (2,400 m)
Battery voltage11 V or more
Throttle position learningCompleted
IAT at engine start - ECT at engine start-7 to 11.1C (-12.6 to 20F)
EVAP VSV and CCVNot operated test by scan tool
Either of the following conditions is metCondition 1 or 2
1. Purge duty cycle8% or more (vary with MAF)
2. Purge concentration for 30 seconds-5 %/% or more when vehicle speed is less than 10 km/h (6.25 mph)
RefuelNot refueled with engine running
FTP12.75 mmHg (-1.7 kPa) or more
ECT at engine start4.4 to 35C (39.9 to 95F)
IAT at engine start4.4 to 35C (39.9 to 95F)
IAT4.4C (39.9F) or more
Vehicle speed changeVehicle is driven by steady speed
Fuel sloshNo sloshing (i.e. fairly smooth road)
Time after engine startWithin 50 minutes
FTP change before vacuum introductionMinimum change
Fuel levelLess than 90 %
TYPICAL MALFUNCTION THRESHOLDS
CCV stuck close P0446:
Duration that the following conditions 1 and 2 are met:4 seconds or more
1. Accumulated purge volume0.5 g or more
2. FTPLess than -12.75 mmHg (-1.7 kPa)
CCV stuck open P0446:
Purge VSV stuck closedDetected

05-202
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
392 Author
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
DTC P0450 EVAPORATIVE EMISSION CONTROL SYS-
TEM PRESSURE SENSOR/SWITCH
DTC P0451 EVAPORATIVE EMISSION CONTROL SYS-
TEM PRESSURE SENSOR RANGE/PER-
FORMANCE
DTC P0452 EVAPORATIVE EMISSION CONTROL SYS-
TEM PRESSURE SENSOR/SWITCH LOW IN-
PUT
DTC P0453 EVAPORATIVE EMISSION CONTROL SYS-
TEM PRESSURE SENSOR/SWITCH HIGH IN-
PUT
DTC SUMMARY
DTCMonitoring ItemsMalfunction Detection ConditionsTrouble AreasDetection Tim-
ingsDetection
Logic
P0450Pressure sensor voltage ab-
normal fluctuationSensor output voltage rapidly fluctuates
beyond upper and lower malfunction
thresholds for 0.5 seconds.
Pump module

Connector/Wire harness
(Pump module - ECM)

ECM
EVAP monitor-
ing (ignition
OFF)

Ignition ON
1 trip
P0451Pressure sensor noisingSensor output voltage fluctuates fre-
quently in certain time period.

Pump module

Connector/Wire harness
(Pump module - ECM)

ECM
EVAP monitor-
ing (ignition
OFF)

Engine running
2 trip
P0451Pressure sensor stuckSensor output voltage does vary in cer-
tain time period.

Pump module

Connector/Wire harness
(Pump module - ECM)

ECM
EVAP monitor-
ing (ignition
OFF)
2 trip
P0452Pressure sensor voltage lowSensor output voltage is less than 0.45
V for 0.5 seconds.

Pump module

Connector/Wire harness
(Pump module - ECM)

ECM
Ignition ON

EVAP monitor-
ing (ignition
OFF)
1 trip
P0453Pressure sensor voltage highSensor output voltage is more than 4.9
V for 0.5 seconds.

Pump module

Connector/Wire harness
(Pump module - ECM)

ECM
Ignition ON

EVAP monitor-
ing (ignition
OFF)
1 trip
HINT:
The pressure sensor is built into the pump module.
CIRCUIT DESCRIPTION
The circuit description can be found in the EVAP (Evaporative Emission) Inspection Procedure (see page
05-317).
05IR9-02

A71562
Pressure Sensor Specification:
Output Voltage
Usable Range
4.900 V
4.150 V
1.425 V
0.450 V
Malfunction Area
Pressure
60
kPa11 0
kPa
Malfunction Area
Standard atmospheric pressure is 101.3 kPaHINT:
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
MONITOR DESCRIPTION
(a) DTC P0450: Pressure sensor voltage abnormal fluctua-
tion.
If the pressure sensor voltage output rapidly fluctuates
between less than 0.45 V and more than 4.9 V, the ECM
interprets this as an open or short circuit malfunction in
the pressure sensor or its circuit, and stops the EVAP
(Evaporative Emission) system monitor. The ECM then il-
luminates the MIL and sets the DTC (1 trip detection log-
ic).
(b) DTC P0451: Pressure sensor noising or stuck
If the pressure sensor voltage output fluctuates rapidly for
10 seconds, the ECM stops the EVAP system monitor.
The ECM interprets this as noise from the pressure sen-
sor, and stops the EVAP system monitor. The ECM then
illuminates the MIL and sets the DTC.
Alternatively, if the sensor voltage output does not
change for 10 seconds, the ECM interprets this as the
sensor being stuck, and stops the monitor. The ECM then
illuminates the MIL and sets the DTC.
(Both the malfunctions are detected by 2 trip detection
logic)
(c) DTC P0452: Pressure sensor voltage low
If the pressure sensor voltage output is below 0.45 V, the
ECM interprets this as an open or short circuit malfunction
in the pressure sensor or its circuit, and stops the EVAP
system monitor. The ECM then illuminates the MIL and
sets the DTC (1 trip detection logic).
(d) DTC P0453: Pressure sensor voltage high
If the pressure sensor voltage output is 4.9 V or more, the
ECM interprets this as an open or short circuit malfunction
in the pressure sensor or its circuit, and stops the EVAP
system monitor. The ECM then illuminates the MIL and
sets the DTC (1 trip detection logic).