TOYOTA HIGHLANDER 2001 Service Repair Manual

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
05-192
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)(From August, 2004)
382 Author
: Date
:
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).

- DIAGNOSTICSSFI SYSTEM (2AZ-FE)(From August, 2004)
05-193
383 Author
: Date
:
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

05-194
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)(From August, 2004)
384 Author
: Date
:
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.

- DIAGNOSTICSSFI SYSTEM (2AZ-FE)(From August, 2004)
05-195
385 Author
: Date
: -MEMO-

A80089
AB B+
Power Transistor
Platinum Hot Wire
(Heater)
Output
Voltage
Temperature
Sensor
Platinum Hot Wire (Heater)
Temperature Sensor
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
05-81
271 Author
: Date
:
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 seconds
Open or short in MAF meter circuit

MAF meter

ECM
P0102When MAF meter circuit has an open for more than 3 seconds
Same as DTC No. P0100
P0103When MAF meter circuit has a short for more than 3 seconds
Same 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 0.0
Open in MAF meter power source circuit

Open or short in VG circuit
271.0 or more
Open in EVG circuit
05ESV-05

05-82
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
272 Author
: Date
:
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

A90347
Y
BatteryFL
MainEngine Room J/BB-W
EFI
RelayM1
MAF Meter
MREL
W-B4 1
WB-R
EVGVG
3
2
1
AEB1
133 1
P-LR
2
52D
J2
J/CL-W30
E7
E7
8
E5ECM
EFI
NO. 1
EHB29 +B
E2GVG 1
EFI NO. 2
22 Engine Room R/B No. 2
12
IK3
W
3
12B 5
2F 3
2I
F7
FL
Block
Assy5 V
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
05-83
273 Author
: Date
:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
WIRING DIAGRAM

A54396
+B (+) Wire Harness Side
M1
MAF Meter
05-84
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
274 Author
: Date
:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help deter-
mine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean
or rich, and other data from the time the malfunction occurred.
1 READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL (MAF RATE)
(a) Connect the hand-held tester or the OBD II scan tool to the DLC3.
(b) Start the engine.
(c) Push the hand-held tester or the OBD II scan tool main switch ON.
(d) On the hand-held tester or the OBD II scan tool, enter the following menus: DIAGNOSIS / ENHANCED
OBD II / DATA LIST / ALL / MAF. Read the values.
Result:
Air Flow Rate (gm/second)Proceed to
0.0A
271.0 or moreB
MAF rate greater than 1 but less than 270.0 *C
HINT:
*: The value must change when the throttle valve is opened or closed.
B Go to step 6
C CHECK FOR INTERMITTENT PROBLEMS
(See page 05-9)
A
2 CHECK MASS AIR FLOW METER (POWER SOUCE VOLTAGE)
(a) Turn the ignition switch ON.
(b) Disconnect the M1 MAF meter connector.
(c) Measure the voltage of the wire harness side connector.
Standard:
Tester ConnectionSpecified Condition
M1-1 (+B) - Body ground9 to 14 V
NG Go to step 5
OK

A76903
VG (+) EVG (-)
E7
ECM
Y
A54396
A81699
A85482
Wire Harness Side
M1
MAF Meter
EVG VG
E7
ECM
EVG
VG
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
05-85
275 Author
: Date
:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
3 INSPECT ECM (VG VOLTAGE)
(a) Start the engine.
(b) Measure the voltage of the ECM connector.
Standard:
Tester ConnectionConditionSpecified Condition
E7-30 (VG) - E7-29 (EVG)Engine is idling0.5 to 3.0 V
HINT:
The shift position should be P or N and the A/C switch should
be turned OFF.
OK REPLACE ECM (See page 10-9)
NG
4 CHECK WIRE HARNESS (MAF METER - ECM)
(a) Disconnect the M1 MAF meter connector.
(b) Disconnect the E7 ECM connector.
(c) Measure the resistance of the wire harness side connec-
tors.
Standard:
Tester ConnectionSpecified Condition
M1-3 (VG) - E7-30 (VG)
M1-2 (EVG) - E7-29 (EVG)Below 1 W
M1-3 (VG) or E7-30 (VG) - Body ground10 kW or higher
NG REPAIR OR REPLACE HARNESS AND
CONNECTOR
OK
REPLACE MASS AIR FLOW METER

A54396
A90291A90959
Wire Harness Side
M1
MAF Meter
+B (+)
EFI RelayEngine Room J/B
A76903
EVG
E7
ECM
05-86
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
276 Author
: Date
:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
5 CHECK WIRE HARNESS (MAF METER - EFI RELAY)
(a) Disconnect the M1 MAF meter connector.
(b) Remove the EFI relay from the engine room J/B.
(c) Measure the resistance of the wire harness side connec-
tors.
Standard:
Tester ConnectionSpecified Condition
M1-1 (+B) - J/B EFI relay terminal 3Below 1 W
M1-1 (+B) or J/B EFI relay terminal 3 -Body ground10 kW or higher
NG REPAIR OR REPLACE HARNESS AND
CONNECTOR
OK
INSPECT ECM POWER SOURCE CIRCUIT (See page 05-312)
6 INSPECT ECM (SENSOR GROUND)
(a) Measure the resistance of the ECM connector.
Standard:
Tester ConnectionSpecified Condition
E7-29 (EVG) - Body groundBelow 1 W
NG REPLACE ECM (See page 10-9)
OK