Page 1409 of 2572
A90344
IGN Fuse Instrument
Panel J/B
Assy
1
5 6 2 3
7 8 4
A56879IG2 AM2
I15
Ignition
Switch
A67446
MREL (+)E1 (-)
E9
ECME5
ECM
05-314
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
504 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
4 CHECK FUSE (IGN)
(a) Remove the IGN fuse from the instrument panel J/B Assy.
(b) Measure the resistance of the IGN fuse.
Standard: Below 1 W
NG REPLACE FUSE
OK
5 INSPECT IGNITION OR STARTER SWITCH ASSY
(a) Measure the resistance of the ignition switch terminals.
Standard:
Switch ConditionTester ConditionSpecified Condition
LOCK6 (IG2) - 7 (AM2)10 kW or higher
ON6 (IG2) - 7 (AM2)Below 1 W
NG REPLACE IGNITION OR STARTER SWITCH
ASSY
OK
CHECK AND REPAIR HARNESS AND CONNECTOR (BATTERY - IGNITION SWITCH, IGNITION
SWITCH - ECM)
6 INSPECT ECM (MREL VOLTAGE)
(a) Turn the ignition switch ON.
(b) Measure the voltage of the ECM connectors.
Standard:
Tester ConnectionSpecified Condition
E5-8 (MREL) - E9-1 (E1)9 to 14 V
NG REPLACE ECM (See page 10-9)
OK
Page 1410 of 2572
A90343
Engine Room J/B
EFI NO. 1 fuse
B60778
5
1
2 312
5
3
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
05-315
505 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
7 CHECK FUSE (EFI NO. 1)
(a) Remove the EFI NO. 1 fuse from the engine room J/B.
(b) Measure the resistance of the EFI NO. 1 fuse.
Standard: Below 1 W
NG REPLACE FUSE
OK
8 INSPECT RELAY (EFI)
(a) Remove the EFI relay from the engine room J/B.
(b) Measure the resistance of the EFI relay.
Standard:
Tester ConnectionSpecified Condition
3 - 510 kW or higher
3 - 5Below 1 W
(when battery voltage is applied to terminals 1 and 2)
NG REPLACE RELAY
OK
Page 1411 of 2572

A90291
A67445
A92643
EFI Relay Wire Harness Side
E5
ECM
MREL
Engine Room J/B
05-316
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
506 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
9 CHECK WIRE HARNESS (EFI RELAY - ECM, EFI RELAY - BODY GROUND)
(a) Check the wire harness between the EFI relay and ECM.
(1) Remove the EFI relay from the engine room J/B.
(2) Disconnect the E5 ECM connector.
(3) Measure the resistance of the wire harness side
connectors.
Standard:
Tester ConnectionSpecified Condition
J/B EFI relay terminal 1 - E5-8 (MREL)Below 1 W
J/B EFI relay terminal 1 or E5-8 (MREL) - Body ground10 kW or higher
(b) Check the wire harness between the EFI relay and body
ground.
(1) Remove the EFI relay from the engine room J/B.
(2) Measure the resistance of the wire harness side
connector and the body ground.
Standard:
Tester ConnectionSpecified Condition
J/B EFI relay terminal 2 - Body groundBelow 1 W
OK REPAIR OR REPLACE HARNESS AND
CONNECTOR
NG
CHECK AND REPAIR HARNESS AND CONNECTOR (TERMINAL +B OF ECM - BATTERY POS-
ITIVE TERMINAL)
Page 1412 of 2572

G30835G32449
E4
Electronically Controlled
Transmission Pattern Select SW
*
SNOW B9 15Multiplex Network
Body ECU
(*) Pattern Select Switch (ECT SNOW Switch)
When the ECT SNOW switch is pushed, the switch contact is made and the ECT SNOW mode is selected.
To cancel the ECT SNOW mode, push the ECT SNOW switch once again. The ECT SNOW mode is automati-
cally cancelled when the ignition switch is turned ºOFFº.Y
3 4 W-B
3D Center J/B
8
3F 13
W-B
IB
- DIAGNOSTICSELECTRONIC CONTROLLED AUTOMATIC
TRANSAXLE [ECT] (U241E/U140F)05-983
1173 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
PATTERN SELECT SWITCH CIRCUIT
CIRCUIT DESCRIPTION
Multiplex network body ECU receives pattern select switch information, and sends it through the multiplex
communication system to the ECM.
ECT SNOW is the system that operates the throttle motor to control engine output to reduce skidding of the
driving wheels, guarantee takeoff acceleration, driving straightness and turning stability.
WIRING DIAGRAM
05ITR-02
Page 1413 of 2572
![TOYOTA HIGHLANDER 2001 Service Repair Manual G23382
Wire Harness Side:
(Connector Front View):
E4
C82813D25463
Switch Side:
(Connector Front View):
E4
05-984- DIAGNOSTICSELECTRONIC CONTROLLED AUTOMATIC
TRANSAXLE [ECT] (U241E/U140F)
1174 Author: TOYOTA HIGHLANDER 2001 Service Repair Manual G23382
Wire Harness Side:
(Connector Front View):
E4
C82813D25463
Switch Side:
(Connector Front View):
E4
05-984- DIAGNOSTICSELECTRONIC CONTROLLED AUTOMATIC
TRANSAXLE [ECT] (U241E/U140F)
1174 Author:](/manual-img/14/57457/w960_57457-1412.png)
G23382
Wire Harness Side:
(Connector Front View):
E4
C82813D25463
Switch Side:
(Connector Front View):
E4
05-984- DIAGNOSTICSELECTRONIC CONTROLLED AUTOMATIC
TRANSAXLE [ECT] (U241E/U140F)
1174 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
1 DRIVING TEST
(a) Start the engine.
(b) Turn the ECT SNOW switch ºOFFº (Normal drive mode).
(c) Confirm vehicle response by driving from a parked position to fully depressing the accelerator pedal.
(d) Turn the ECT SNOW switch ºONº and perform the same check as (c).
Confirm that there is a difference between ECT SNOW switch ºONº and ºOFFº.
HINT:
Driving test should be done on a paved road (a nonskid road).
Make sure not to use the TRAC system when testing a vehicle equipped with one.
OK:
There is a difference in acceleration between ºONº and ºOFFº.
NG Go to step 2
OK
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
(SEE PAGE 05-904)
2 CHECK HARNESS AND CONNECTOR(PATTERN SELECT SWITCH ASSY NO.1 -
BODY GROUND)
(a) Disconnect the connector of pattern select switch (ECT
SNOW switch).
(b) Measure the resistance according to the value(s) in the
table below.
Standard:
Tester ConnectionSpecified Condition
4 - Body groundBelow 1 W
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR (SEE PAGE 01-36)
OK
3 INSPECT PATTERN SELECT SWITCH ASSY NO.1
(a) Measure the resistance according to the value(s) in the
table below.
Standard:
Switch ConditionTester ConnectionSpecified Condition
Press continuously
Pattern select switch
34
Below 1 W
Release
Pattern select switch3 - 4
10 kW or higher
NG REPLACE PATTERN SELECT SWITCH ASSY
NO.1
OK
Page 1414 of 2572
G32072
B9
B9
SNOW
Multiplex Network Body ECU:
Back Side:
- DIAGNOSTICSELECTRONIC CONTROLLED AUTOMATIC
TRANSAXLE [ECT] (U241E/U140F)05-985
1175 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
4 CHECK HARNESS AND CONNECTOR(PATTERN SELECT SWITCH ASSY NO.1 -
MULTIPLEX NETWORK BODY ECU)
(a) Connect the connector of pattern select switch (ECT
SNOW switch).
(b) Disconnect the multiplex network body ECU connector.
(c) Measure the resistance between terminals SNOW of mul-
tiplex network body ECU and body ground.
Standard:
Switch ConditionTester ConnectionSpecified Condition
Press continuously
Pattern select switch
B9 - 15 (SNOW) - Below 1 W
Release
Pattern select switch
B9 15 (SNOW)
Body ground
10 kW or higher
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR (SEE PAGE 01-36)
OK
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
(SEE PAGE 05-904)
Page 1415 of 2572

0.02 inch orifice clogged
Pressure sensor low outputP043E
P043FP0441 P0451 P0452 P0453 P0455 P0456 P2419P2401
P2402
0.02 inch orifice high-flow
Pressure sensor stuck
Pressure sensor noise
Gross leak
Small leak
Vacuum pump stuck OFF
Vacuum pump stuck ON
Vent valve stuck closed
Vent valve stuck open (vent) Purge VSV stuck open
Purge VSV stuck closed
Pressure sensor high output
DTCs
Malfunctioning AreasP2420 P0450
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
05-317
507 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
EVAP INSPECTION PROCEDURE
DTCS RELATING TO EVAP SYSTEM
DTCsMonitoring ItemsSee Page
P043E0.02 inch orifice clogged (built into pump module)05-190
P043F0.02 inch orifice high-flow (built into pump module)05-190
P0441
Purge VSV (Vacuum Switching Valve) stuck closed
Purge VSV stuck open
Purge flow
05-196
P0450Pressure sensor (built into pump module) voltage abnormal fluctuation05-202
P0451Pressure sensor (built into pump module) noising
Pressure sensor stuck (built into pump module)05-202
P0452Pressure sensor (built into pump module) voltage low05-202
P0453Pressure sensor (built into pump module) voltage high05-202
P0455EVAP gross leak05-21 1
P0456EVAP small leak05-21 1
P2401Vacuum pump stuck OFF (built into pump module)05-288
P2402Vacuum pump stuck ON (built into pump module)05-288
P2419Vent valve stuck closed (built into pump module)05-294
P2420Vent valve stuck open (vent) (built into pump module)05-294
P2610Soak timer (built into ECM)05-300
If any EVAP system DTCs are set, the malfunctioning area can be determined using the table below.
NOTICE:
If the 0.02 inch reference pressure difference between the first and second checks is greater than
the specification, the DTCs corresponding to the reference pressure (P043E, P043F, P0441, P0455,
P0456, P2401, P2420) will be all stored.
05IRG-02
Page 1416 of 2572

A93865Purge VSV
EVAP Hose
(To Throttle Body)
EVAP Hose
(From Canister)
Vent ValveCanister
Air Filter
Pump ModulePressure Sensor
Vacuum Pump
Purge Line
Refueling Valve
Fuel Tank
Fuel Cap
Location of EVAP (Evaporative Emission) system:
A93866
EVAP System Circuit
Intake Manifold
Purge VSV
Cut-of f Valve Roll-over Valve
CanisterAir FilterFuel Cap
Service Port
Air Cleaner
Restrictor (0.08 inch)
Refueling Valve Throttle Valve
ECM
Soak Timer
Pump Module (refer to fig. 1)
Fuel Tank 05-318
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
508 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
CIRCUIT DESCRIPTION
While the engine is running, if a predetermined condition (closed-loop, etc.) is met, the purge VSV is opened
by the ECM and stored fuel vapors in the canister are purged to the intake manifold. The ECM changes the
duty cycle ratio of the purge VSV to control purge flow volume.
The purge flow volume is also determined by the intake manifold pressure.
Atmospheric pressure is allowed
into the canister through the vent valve to ensure that the purge flow is maintained when the negative pres-
sure (vacuum) is applied to the canister.
The following two monitors run to confirm appropriate EVAP system operation.