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DTC P043E EVAPORATIVE EMISSION SYSTEM
REFERENCE ORIFICE CLOG UP
DTC P043F EVAPORATIVE EMISSION SYSTEM
REFERENCE ORIFICE HIGH FLOW
CIRCUIT DESCRIPTION
Refer to EVAP Inspection Procedure (see page 05-317).
DTCsMonitoring ItemDetection ConditionTrouble AreaDetection
TimingDetection
Period
P043E0.02 inch orifice clogged
(built-in pump module)
To determine leak criterion (Reference
pressure), vacuum pump creates negative
pressure in canister pump module through
0.02 inch orifice and pressure is measured.
If one of following conditions is met, ECM
setspumpmodule related DTCs: P043E
Pump module
Connector / wire harness
Ignition2 trips
P043F0.02 inch orifice high-flow
(built-in pump module)
sets pump module related DTCs: P043E,
P043F, P2401, P2402 and P2419:
Reference pressure is -1 kPa or higher
Reference pressure is -4.85 kPa or lower
Reference pressure is not saturated within
60 secondsConnector / wire harness
(Pump module - ECM)
ECM
Ignition
OFF2 trips
WIRING DIAGRAM
Refer to EVAP Inspection Procedure (see page 05-317).
INSPECTION PROCEDURE
Refer to EVAP Inspection Procedure (see page 05-317).
05PGO-01
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A96746
Fuel Tank Canister
Vacuum Pump: OFF Pressure Sensor 0.02 Inch Orifice
Pump Module
Operation A: Atmospheric Pressure Measurement
Vent Valve: OFF (vent)
Operation D: Purge VSV monitor Operation B, E: 0.02 Inch Leak Pressure Measurement
Negative
Pressure Atmospheric
Pressure
Operation C: EVAP System Pressure Measurement
Air Filter
Purge VSV: OFFOFF (vent)
ON
OFF
OFF
ON
ON (closed)ON
ON
ON (closed)
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)(From August, 2004)
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MONITOR DESCRIPTION
5 hours* after the ignition switch is turned OFF, the electric vacuum pump creates negative pressure (vacu-
um) in the EVAP (Evaporative Emission) system. The ECM monitors for leaks and actuator malfunctions
based on the EVAP pressure.
HINT:
*: If the engine coolant temperature is not below 35C (95F) after 5 hours after the ignition switch is turned
off, the monitor check starts 2 hours later. If it is still not below 35C (95F) 7 hours after the ignition switch
is turned off, the monitor check starts 2.5 hours later.
SequenceOperationsDescriptionsDuration
-ECM activationActivated by soak timer, 5 hours (7 or 9.5 hours) after ignition switch turned to OFF.-
AAtmospheric pressure
measurement
Vent valve turned OFF (vent) and EVAP system pressure measured by ECM in order to
register atmospheric pressure.
If EVAP pressure is not between 70 kPa and 110 kPa (525 mmHg and 825 mmHg), ECM
cancels EVAP system monitor.
10 seconds
B
First 0.02 inch leak
pressure measure-
mentIn order to determine 0.02 inch leak pressure standard, vacuum pump creates negative pres-
sure (vacuum) through 0.02 inch orifice and then ECM checks if vacuum pump and vent
valve operate normally.
60 seconds
CEVAP system pres-
sure measurement
Vent valve turned ON (closed) to shut EVAP system.
Negative pressure (vacuum) created in EVAP system, and EVAP system pressure then
measured.
Write down the measured value as it will be used in the leak check.
If EVAP pressure does not stabilize within 15 minutes, ECM cancels EVAP system monitor.
15 minutes*
DPurge VSV monitorPurge VSV opened and then EVAP system pressure measured by ECM.
Large increase indicates normal.10 seconds
E
Second 0.02 inch leak
pressure measure-
mentLeak check is performed after second 0.02 inch leak pressure standard is measured.
If stabilized system pressure higher than second 0.02 inch leak pressure standard, ECM
determines that EVAP system leaking.
60 seconds
FFinal checkAtmospheric pressure measured and then monitoring result recorded by ECM.-
* If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.
Page 1651 of 2572
A85217
Purge VSV
Vent Valve
Vacuum Pump
EVAP Pressure
secOFF
Sequence
TimeA
10
sec60
Within 15 minutes
sec ON
Specified
RangeBCD
EVAP Pressure during EVAP Monitor
OK
Malfunction
ON: Open
OFF: Closed
OFF: Vent ON: Closed
10
sec60
E Malfunction
OFF
OFF
ON OFF
OK
Malfunction
Malfunction
-1 kPa
-4.85 kPa
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In sequence B and E, to determine the leak criterion, the vacuum pump creates negative pressure in the
canister pump module through the 0.02 inch orifice. If the pressure is out of specified range or is not satu-
rated, the ECM illuminates the MIL and sets DTCs P043E, P043F, P2401, P2402 and P2419 (2-trip detec-
tion logic).
Page 1652 of 2572

- DIAGNOSTICSSFI SYSTEM (2AZ-FE)(From August, 2004)
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OBD II MONITOR SPECIFICATIONS
Monitor Strategy
Required Sensors/ComponentsPump module
Frequency of OperationOnce per driving cycle
DurationWithin 15 minutes (varies with amount of 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
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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
Following values are when atmosperic pressure is 760
mmHg (100 kPa)-
One of the following conditions is met:Condition 1, 2, 3, 4 or 5
1. FTP when 4 seconds after reference pressure measure-
ment beganMore than -7.5 mmHg (-1 kPa)
2. Reference pressureLess than -36.4 mmHg (-4.85 kPa)
3. Reference pressure-7.9 mmHg (-1.057 kPa) or more
4. Reference pressureNot saturated
5. Reference pressure difference between first and second5.3 mmHg (0.7 kPa) or more
MONITOR RESULT (MODE 06)
Refer to page 05-317 for detailed information on Monitor Result.
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A80089
AB B+
Power Transistor
Platinum Hot Wire
(Heater)
Output
Voltage
Temperature
Sensor
Platinum Hot Wire (Heater)
Temperature Sensor
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
DTC P0100 MASS OR VOLUME AIR FLOW CIRCUIT
DTC P0102 MASS OR VOLUME AIR FLOW CIRCUIT
LOW INPUT
DTC P0103 MASS OR VOLUME AIR FLOW CIRCUIT
HIGH INPUT
CIRCUIT DESCRIPTION
The Mass Air Flow (MAF) meter measures the amount of air flowing through the throttle valve. The ECM uses
this information to determine the fuel injection time and provide a proper air fuel ratio. Inside the MAF meter,
there is a heated platinum wire exposed to the flow of intake air.
By applying a specific current to the wire, the ECM heats this wire to a given temperature. The flow of incom-
ing air cools the wire and an internal thermistor, changing their resistance. To maintain a constant current
value, the ECM varies the voltage applied to these components in the MAF meter. The voltage level is pro-
portional to the air flow through the sensor. The ECM interprets this voltage as the intake air amount.
The circuit is constructed so that the platinum hot wire and temperature sensor provide a bridge circuit, with
the power transistor controlled so that the potential of A and B remains equal to maintain the set temperature.
DTC No.DTC Detection ConditionTrouble Area
P0100When MAF meter circuit has an open or a short for more than
3 secondsOpen or short in MAF meter circuit
MAF meter
ECM
P0102When MAF meter circuit has an open for more than 3 secondsSame as DTC No. P0100
P0103When MAF meter circuit has a short for more than 3 secondsSame as DTC No. P0100
HINT:
After confirming DTC P0100, P0102 or P0103, use the hand-held tester or the OBD II scan tool to confirm
the MAF ratio from the ALL menu (to reach the ALL menu: DIAGNOSIS / ENHANCED OBD II / DATA LIST
/ ALL).
Air Flow Value (g/s)Malfunction
Approximately 0.0Open in MAF meter power source circuit
Open or short in VG circuit
271.0 or moreOpen in EVG circuit
05ESV-05
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
MONITOR DESCRIPTION
If there is a defect in the sensor, or an open or short circuit, the voltage level will deviate from the normal
operating range. The ECM interprets this deviation as a defect in the MAF meter and sets a DTC.
Example:
The sensor voltage output is less than 0.2 V or more than 4.9 V and either condition continues for more than
3 seconds.
MONITOR STRATEGY
Related DTCs
P0100: MAF meter range check (Chattering)
P0102: MAF meter range check(Low voltage)
P0103: MAF meter range check (High voltage)
Required sensors / components (Main)MAF Meter
Required sensors / components (Related)CKP (Crank shaft position) sensor
Frequency of operationContinuous
Duration3 sec.
MIL operationImmediate: Engine RPM is less than 4,000 rpm
2 driving cycles: Engine RPM is 4,000 rpm or more
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
The monitor will run whenever these DTCs are not presentSee page 05-16
TYPICAL MALFUNCTION THRESHOLDS
P0100:
MAF meter voltageLess than 0.2 V, or more than 4.9 V
P0102:
MAF meter voltageLess than 0.2 V
P0103:
MAF meter voltageMore than 4.9 V
COMPONENT OPERATING RANGE
MAF meter voltageBetween 0.4 and 2.2 V