engine TOYOTA SIENNA 2007 Service Repair Manual

ES–2702GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
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DTC SUMMARY
DESCRIPTION
The circuit description can be found in the EVAP (Evaporative Emission) System (See page ES-409).
INSPECTION PROCEDURE
Refer to the EVAP System (See page ES-412).
MONITOR DESCRIPTION
The two monitors, Key-Off and Purge Flow, are used to detect malfunctions relating to DTC P0441. The
Key-off monitor is initiated by the ECM internal timer, known as the soak timer, 5 hours
*1 after the ignition
switch is turned off. The purge flow monitor runs while the engine is running.
DTC P0441Evaporative Emission Control System Incorrect
Purge Flow
DTCs Monitoring Item Malfunction Detection Condition Trouble AreaDetection
TimingDetection
Logic
P0441Purge VSV (Vacuum
Switching Valve) stuck
openVacuum pump creates negative pressure
(vacuum) in EVAP system and EVAP
system pressure is measured. 0.02 inch
leak pressure standard is measured at
start and end of leak check.
If stabilized pressure is higher than
[second 0.02 inch leak pressure
standard x 0.2], ECM determines that
purge VSV is stuck open
• Purge VSV
• Purge VSV circuit
(between purge VSV
and ECM)
• Leakage from EVAP
line (between purge
VSV and intake
manifold)
• EVAP line clogged
(between purge VSV
and canister)
•ECMWhile
ignition
switch OFF2 trip
P0441 Purge VSV stuck closedAfter EVAP leak check is performed,
purge VSV is turned ON (open), and
atmospheric air is introduced into EVAP
system. 0.02 inch leak pressure standard
is measured at the start and end of leak
check.
If pressure does not return to near
atmospheric pressure, ECM determines
that purge valve is stuck closedWhile
ignition
switch OFF2 trip
P0441 Purge flowWhile engine running, the following
conditions are successively met:
• Negative pressure is not created in
EVAP system when purge VSV is
turned ON (open)
• EVAP system pressure change is
less than 0.5 kPa (3.75 mmHg) when
vent valve is turned ON (closed)
• Atmospheric pressure change before
and after purge flow monitor is less
than 0.1 kPa (0.75 mmHg)While
ignition
switch OFF2 trip

2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEMES–271
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1. KEY-OFF MONITOR
5 hours
*1 after the ignition switch is turned off, the electric vacuum pump creates negative pressure
(vacuum) in the EVAP (Evaporative Emission) system. The ECM monitors for leaks and actuator
malfunctions based on the EVAP pressure.
HINT:
*1: If the engine coolant temperature is not below 35C (95F) 5 hours after the ignition switch is
turned off, the monitor check starts 2 hours later. If it is still not below 35
C (95F) 7 hours after the
ignition switch is turned off, the monitor check starts 2.5 hours later.
*2: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.
Sequence Operation Description Duration
- ECM activationActivated by soak timer, 5 hours (7 or 9.5 hours) after ignition switch
turned off.-
AAtmospheric pressure
measurementVent valve is turned OFF (vent) and EVAP system pressure is
measured by ECM in order to register atmospheric pressure.
If pressure in EVAP system is not between 70 kPa and 110 kPa (525
mmHg and 825 mmHg), ECM cancels EVAP system monitor.10 seconds
BFirst 0.02 inch leak pressure
measurementIn order to determine 0.02 inch leak pressure standard, vacuum pump
creates negative pressure (vacuum) through 0.02 inch orifice and then
ECM checks if vacuum pump and vent valve operate normally.60 seconds
CEVAP system pressure
measurementVent valve is turned ON (closed) to shut EVAP system.
Negative pressure (vacuum) is created in EVAP system, and EVAP
system pressure is then measured.
Write down measured value as it will be used in leak check.
If EVAP pressure does not stabilize within 15 minutes, ECM cancels
EVAP system monitor.15 minutes
*2
D Purge VSV monitorPurge VSV is opened and then EVAP system pressure is measured
by ECM.
Large increase indicates normal.10 seconds
ESecond 0.02 inch leak pressure
measurementAfter second 0.02 inch leak pressure measurement, leak check is
performed by comparing first and second 0.02 inch leak pressure
standards.
If stabilized system pressure is higher than second 0.02 inch leak
pressure standard, ECM determines that EVAP system leaking.60 seconds
F Final checkAtmospheric pressure is measured and then monitoring result is
recorded by ECM.-

ES–2722GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
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2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEMES–273
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(a) Purge VSV stuck open
In operation C, the vacuum pump creates negative pressure (vacuum) in the EVAP (Evaporative
Emission) system. The EVAP system pressure is then measured by the ECM using the pressure
sensor. If the stabilized system pressure is higher than [second 0.02 inch leak pressure standard
x 0.2], the ECM interprets this as the purge VSV (Vacuum Switching Valve) being stuck open.
The ECM illuminates the MIL and sets the DTC (2 trip detection logic).
G036775E09

ES–2742GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
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(b) Purge VSV stuck closed
In operation D, the pressure sensor measures the EVAP (Evaporative Emission) system
pressure. The pressure measurement for purge VSV monitor is begun when the purge VSV is
turned on (open) after the EVAP leak check. When the measured pressure indicates an increase
of 0.3 kPa (2.25 mmHg) or more, the purge VSV is functioning normally. If the pressure does not
increase, the ECM interprets this as the purge VSV being stuck closed. The ECM illuminates the
MIL and sets the DTC (2 trip detection logic).
2. PURGE FLOW MONITOR
The purge flow monitor consists of the two step monitors.
The 1st monitor is conducted every time and the 2nd
monitor is activated if necessary.
• The 1st monitor
While the engine is running and the purge VSV
(Vacuum Switching Valve) is on (open), the ECM
monitors the purge flow by measuring the EVAP
pressure change. If negative pressure is not created,
the ECM begins the 2nd monitor.
• The 2nd monitor
The vent valve is turned on (closed) and the EVAP
pressure is then measured. If the variation in the
pressure is less than 0.5 kPa (3.75 mmHg), the ECM
interprets this as the purge VSV being stuck closed,
and illuminates the MIL and sets DTC P0441 (2 trip
detection logic).
Atmospheric pressure check:
In order to ensure reliable malfunction detection, the
variation between the atmospheric pressures, before
and after conduction of the purge flow monitor, is
measured by the ECM.
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2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEMES–275
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MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
All:
Purge flow:
Purge VSV stuck open and closed:
Key-off monitor sequence 1 to 8
1. Atmospheric pressure measurement
Related DTCsP0441: Purge VSV stuck open
P0441: Purge VSV stuck closed
P0441: Purge flow
Required Sensors / Components Purge VSV and pump module
Frequency of Operation Once per driving cycle
Duration Within 15 minutes
MIL Operation 2 driving cycles
Sequence of Operation None
The monitor is run whenever this DTC is not presentP0011, P0012 (VVT System 1-Advance, Retard), P0021, P0022 (VVT System 2-
Adavance, Retard), P0100, P0101, P0102, P0103 (MAF Sensor), P0110, P0112,
P0113 (IAT Sensor), P0115, P0116, P0117, P0118 (ECT Sensor), P0120, P0121,
P0122, P0123, P0220, P0222, P0223 , P2135 (TP Sensor), P0125 (Insufficient ECT
for Closed Loop), P0171,P0172 (Fuel System), P0300, P0301, P0302, P0303,
P0304, P0305, P0306 (Misfire), P0335 (CKP Sensor), P0340 (CMP Sensor), P0351,
P0352, P0353, P0354, P0355, P0356 (Ignitor), P0450, P0451, P0452, P0453 (EVAP
pressure Sensor), P0500 (VSS)
Engine Running
ECT 4.4
C (40F) or more
IAT 4.4
C (40F) or more
EVAP pressure sensor Not detected
EVAP canister purge valve Not operated by scan tool
EVAP system check Not operated by scan tool
Battery voltage 10 V or more
Purge duty cycle 8% or more
Atmospheric pressure 70 to 110 kPa (525 to 825 mmHg)
Battery voltage 10.5 V or more
Vehicle speed Less than 2.5 mph (4 km/h)
Ignition switch OFF
Time after key-off 5 or 7 or 9.5 hours
EVAP pressure sensor malfunction (P0450, P0452,
P0453)Not detected
EVAP canister purge valve Not operated by scan tool
EVAP canister vent valve Not operated by scan tool
EVAP leak detection pump Not operated by scan tool
Both of the following conditions 1 and 2 are met before
key-off-
1. Duration that vehicle driven 5 minutes or more
2. EVAP purge operation Performed
ECT 4.4 to 35
C (40 to 95F)
IAT 4.4 to 35
C (40 to 95F)
Next sequence is run if the following condition is met -
Atmospheric pressure change Less than 0.3 kPa (2.25 mmHg) in 1 second

ES–2762GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
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2. First reference pressure measurement
3. EVAP canister vent valve close stuck check
4. Vacuum introduction
5. EVAP canister purge valve close stuck check
6. Second reference pressure measurement
7. Leak check
8. Atmospheric pressure measurement
TYPICAL MALFUNCTION THRESHOLDS
Purge flow:
EVAP VSV stuck open:
EVAP VSV stuck closed:
MONITOR RESULT
Refer to CHECKING MONITOR STATUS (See page ES-19).
Next sequence is run if the following conditions are met Conditions 1, 2 and 3
1. EVAP pressure just after reference pressure
measurement-1 kPa (-7.5 mmHg) or less
2. Reference pressure -4.85 to -1.057 kPa (-36.384 to -7.929 mmHg)
3. Reference pressure Saturated within 1 minute
Next sequence is run if the following condition is met -
EVAP pressure change after vent valve is ON 0.3 kPa (2.25 mmHg) or more
Next sequence is run if the following condition is met -
EVAP pressure Saturated within 15 minutes
Next sequence is run if the following condition is met -
EVAP pressure change after purge valve is open 0.3 kPa (2.25 mmHg) or more
Next sequence is run if the following conditions are met Conditions 1, 2, 3 and 4
1. EVAP pressure just after reference pressure
measurement-1 kPa (-7.5 mmHg) or less
2. Reference pressure -4.85 to -1.057 kPa (-36.384 to -7.929 mmHg)
3. Reference pressure Saturated
4. Difference between first reference pressure and
second reference pressureLess than 0.7 kPa (5.25 mmHg)
Next sequence is run if the following condition is met -
EVAP pressure when vacuum introduction was
completeLower than second reference pressure
EVAP monitor is complete if the following condition is
met-
Atmospheric pressure difference between sequence 1
and 8Within 0.3 kPa (2.25 mmHg)
Both of the following conditions are met Conditions (a) and (b)
(a) EVAP pressure change when purge flow is started Less than 0.1 kPa (0.75 mmHg)
(b) EVAP pressure change during purge flow when
EVAP pressure switching valve ON (closed)Less than 0.5 kPa (3.75 mmHg)
EVAP pressure when vacuum introduction is complete Higher than reference pressure x 0.2
EVAP pressure change after EVAP canister purge
valve is openLess than 0.3 kPa (2.25 mmHg)

2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEMES–277
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DTC SUMMARY
HINT:
The canister pressure sensor is built into the canister pump module.
DESCRIPTION
The description can be found in the EVAP (Evaporative Emission) System (See page ES-409).
DTC P0450Evaporative Emission Control System Pressure
Sensor / Switch
DTC P0451Evaporative Emission Control System Pressure
Sensor Range / Performance
DTC P0452Evaporative Emission Control System Pressure
Sensor / Switch Low Input
DTC P0453Evaporative Emission Control System Pressure
Sensor / Switch High Input
DTCs Monitoring ItemMalfunction Detection
ConditionTrouble Area Detection TimingDetection
Logic
P0450Pressure sensor abnormal
voltage fluctuationSensor output voltage rapidly
fluctuates beyond upper and
lower malfunction thresholds for
0.5 seconds.• Pump module
•ECM• EVAP
monitoring
(ignition switch
OFF)
• Ignition switch
ON1 trip
P0451Pressure sensor abnormal
voltage fluctuationSensor output voltage fluctuates
frequently in a certain time period.
• Pump module
• Connector/wire
harness (Pump
module - ECM)
•ECM• EVAP
monitoring
(ignition switch
OFF)
• Engine running2 trip
P0451Pressure sensor constant
voltageSensor output voltage does not
vary in a certain time period.EVAP monitoring
(ignition switch
OFF)2 trip
P0452Pressure sensor voltage
lowSensor output voltage is less than
0.45 V for 0.5 seconds.• Ignition switch
ON
• EVAP
monitoring
(ignition switch
OFF)1 trip
P0453Pressure sensor voltage
highSensor output voltage is more
than 4.9 V for 0.5 seconds.• Ignition switch
ON
• EVAP
monitoring
(ignition switch
OFF)1 trip

ES–2782GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
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MONITOR DESCRIPTION
1. DTC P0450: Pressure sensor abnormal voltage fluctuation
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 illuminates the MIL and sets
the DTC (1 trip detection logic).
2. DTC P0451: Pressure sensor abnormal voltage fluctuation or being constant
If the pressure sensor voltage output fluctuates rapidly for 10 seconds, the ECM stops the EVAP
system monitor. The ECM interprets this as the pressure sensor voltage fluctuating, 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.)
3. 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).
4. 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).
MONITOR STRATEGY
Related DTCsP0450: Evaporative emission control system pressure sensor/switch chattering
P0451: Evaporative emission control system pressure sensor noise
P0451: Evaporative emission control system pressure sensor stuck
P0452: Evaporative emission control system pressure sensor/switch low input
P0453: Evaporative emission control system pressure sensor/switch high input
Required Sensors / Components Pump module
Frequency of OperationOnce per driving cycle: P0451 sensor stuck
Continuous: P0451 sensor noising, P0450, P0452 and P0453
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2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEMES–279
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TYPICAL ENABLING CONDITIONS
All:
P0451 (Noise monitor):
P0451 (Stuck monitor):
P0450, P0452 and P0453:
TYPICAL MALFUNCTION THRESHOLDS
(a) P0450: Pressure sensor chattering
(b) P0451: Pressure sensor noise
(c) P0451: Pressure sensor stuck
(d) P0452: Pressure sensor low voltage
(e) P0453: Pressure sensor high voltage
DurationLess than 15 seconds: P0451 (Pressure sensor noise)
Within 2 minutes: P0451 (Pressure sensor stuck)
0.5 seconds: P0450, P0452, P0453
MIL OperationImmediate: P0450, P0452, P0453
2 driving cycles: P0451
Sequence of Operation None
The monitor will run whenever these DTCs are not
presentNone
Atmospheric pressure 70 to 110 kPa (525 to 825 mmHg)
Battery voltage 10.5 V or more
IAT 4.4 to 35
C (40 to 95F)
EVAP pressure sensor malfunction (P0450, P0452,
P0453)Not detected
Either of the following conditions 1 or 2 is met -
1. Engine condition Running
2. Time after key-off 5 or 7 or 9.5 hours
Battery voltage 10.5 V or more
IAT 4.4 to 35
C (40 to 95F)
EVAP pressure sensor malfunction (P0450, P0452,
P0453)Not detected
Atmospheric pressure 70 to 110 kPa (525 to 825 mmHg)
Time after key-off 5 or 7 or 9.5 hours
Ignition switch ON
Battery voltage 8 V or more
Sta r t e r OF F
EVAP pressure Less than 42.11 kPa (316 mmHg), or more than 123.761 kPa (928 mmHg)
Frequency that EVAP pressure change is 0.3 kPa (2.25
mmHg) or more10 times or more in 10 seconds
EVAP pressure change during reference pressure
measurementLess than 0.65 kPa (4.876 mmHg)
EVAP pressure Less than 42.11 kPa (316 mmHg)
EVAP pressure More than 123.761 kPa (928 mmHg)