Page 1513 of 2572
F45107
Repair Wire
- DIAGNOSTICSCAN COMMUNICATION SYSTEM
05-2091
2281 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
(b) If it is impossible to check resistance from the back of the
connector, use a repair wire to check it.
Page 1514 of 2572

052IA-27
- DIAGNOSTICSENGINE IMMOBILIZER SYSTEM
05-1985
2175 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
ENGINE IMMOBILIZER SYSTEM
HOW TO PROCEED WITH TROUBLESHOOTING
HINT:
Use this procedure to troubleshoot the engine immobilizer system.
1 VEHICLE BROUGHT TO WORKSHOP
2 CUSTOMER PROBLEM ANALYSIS CHECK AND SYMPTOM CHECK
(see page 05-1987)
3 CRANK ENGINE FOR MORE THAN 10 SECONDS
4 CHECK DTC
(a) Check for DTCs and note any codes that are output.
(b) Delete the DTC.
(c) Recheck for DTCs. Try to prompt the DTC (SFI system and engine immobilizer system) by simulating
the original activity that the DTC suggested.
(1) If the DTC does not reoccur, proceed to A.
(2) If the DTC (SFI system) reoccurs, proceed to B.
(3) If the DTC (engine immobilizer system) reoccur, proceed to C.
B Go to SFI SYSTEM
(2AZ-FE engine: See page 05-1)
(3MZ-FE engine: See page 05-362)
C Go to step 8
A
5 READ VALUE OF HAND-HELD TESTER
(IMMOBILIZER ECU (TRANSPONDER KEY ECU ASSY) (SWITCH CONDITION))
(a) Connect the hand-held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand-held tester main switch ON.
(c) Select the item ºKEY SWº in the ºDATA LISTº and read its value displayed on the hand-held tester.
Transponder key ECU assy:
ItemMeasurement Item/
Display (Range)Normal ConditionDiagnostic Note
KEY SwitchUnlock warning switch signal
/ON or OFFON: Key is in ignition key cylinder
OFF: No key is in ignition key cyl-
inder
-
NG Go to DTC B2780 (see page 05-1998)
Page 1515 of 2572
05-1986
- DIAGNOSTICSENGINE IMMOBILIZER SYSTEM
2176 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
OK
6 PROBLEM SYMPTOMS TABLE (see page 05-1997)
(a) When the problem is not listed on the problem symptoms table, proceed to A.
(b) When the problem is listed on the problem symptoms table, proceed to B.
B Go to step 8
A
7 PERFORM TROUBLESHOOTING ACCORDING TO MALFUNCTION SYMPTOM
(a) Pre-check (see page 05-1988)
(1) Inspect with the hand-held tester (ECU data monitor).
(2) Inspect with the hand-held tester (ACTIVE TEST).
(b) Terminals of ECU
(see page 05-1993)
8 ADJUST, REPAIR OR REPLACE
END
Page 1516 of 2572
B78723
KSW
DCTY
MPX1
MPX2 B10
B11
B92
11
6
10 G
B J6
J/C
D
B
B10 D
9
IA1 K4
Un-lock Warning
Switch Assy
1 9
7
14G
Combination Meter Assy
21
C11 Door Open
IndicatorMPX Line D7
Front Door Courtesy
Lamp Switch Assy (Driver Side)2 W-B
4L
4N
9
C12 W-B
W-B
MPX Line IC
YOW SB
MPX+
MPX-1Multiplex Network
Body ECU
Passenger Side J/B
G
- DIAGNOSTICSPOWER DOOR LOCK CONTROL SYSTEM
05-1957
2147 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
KEY CONFINEMENT PREVENTION FUNCTION DOES NOT WORK
PROPERLY (MANUAL OPERATION AND INTERLOCKED WITH
KEY ARE ACTIVE)
CIRCUIT DESCRIPTION
The multiplex network body ECU senses, by the un-lock warning switch, that the ignition key is in the key
cylinder. Because of this, the multiplex network body ECU will unlock all the doors immediately after locking
them if a door has been locked while the key is in the ignition key cylinder.
WIRING DIAGRAM
0526N-02
Page 1517 of 2572
B52271
ON OFF
B61511
B10
05-1958
- DIAGNOSTICSPOWER DOOR LOCK CONTROL SYSTEM
2148 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
1 CHECK MANUAL DOOR LOCK OPERATION
NG GO TO POWER WINDOW CONTROL SYSTEM
(See page 05-1912)
OK
2 INSPECT UN-LOCK WARNING SWITCH ASSY
(a) Inspect the un-lock warning switch continuity.
Standard:
ConditionTester ConnectionSpecified Condition
Switch OFF
(Key removed)-No continuity
Switch ON
(Key set)1 @ 2Continuity
NG REPLACE UN-LOCK WARNING SWITCH ASSY
OK
3 CHECK MULTIPLEX NETWORK BODY ECU
(a) Disconnect the multiplex network body ECU B10 connec-
tor and inspect the body ECU B10-2 terminal.
Standard:
Tester ConnectionConditionSpecified Condition
B10-2 @ Body groundConstant12 - 14 V
NG REPLACE MULTIPLEX NETWORK BODY ECU
OK
Page 1518 of 2572
Wire Harness Side
B51904
- DIAGNOSTICSPOWER DOOR LOCK CONTROL SYSTEM
05-1959
2149 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
4 CHECK WIRE HARNESS
(a) Disconnect the un-lock warning switch connector and in-
spect the connector on the wire harness side.
Standard:
Tester ConnectionConditionSpecified Condition
2 @ Body groundConstant10 - 14 V
1 @ Body groundConstantContinuity
NG REPAIR OR REPLACE HARNESS AND
CONNECTOR
OK
5 CHECK DOOR OPEN WARNING LIGHT
(a) Check that the door open warning light will be on when the driver door is opened.
OK REPLACE MULTIPLEX NETWORK BODY ECU
NG
6 INSPECT FRONT DOOR COURTESY LAMP SWITCH ASSY
(a) Inspect the door courtesy lamp switch continuity.
Standard:
Switch PositionSpecified Condition
ON (switch pin released: opened door)Continuity
OFF (switch pin pushed in: closed door)No continuity
NG REPLACE FRONT DOOR COURTESY LAMP
SWITCH ASSY
OK
REPAIR OR REPLACE WIRE HARNESS (COURTESY LIGHT SWITCH - BODY ECU)
Page 1519 of 2572
B80391
G K4
Unlock Warning
Switch
1
2 W-B
Body ECUG
KSW DD
D
ICW-B 4L 4G 9
4N12
T4 Theft Warning ECU Assy
J6
J/C
Passenger Side J/BP
IL218
W-B17
- DIAGNOSTICSTHEFT DETERRENT SYSTEM
05-2033
2223 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
UNLOCK WARNING SWITCH CIRCUIT
CIRCUIT DESCRIPTION
The key unlock warning switch comes on when the ignition key is inserted in the ignition key cylinder and
goes off when the ignition key is removed.
The ECU operates the key confinement prevention function while the key unlock warning switch is on.
WIRING DIAGRAM
05ITN-03
Page 1520 of 2572
B51581
Not Pushed
(ON)
Pushed
(OFF)
21
3 4
B77247
Wire Harness Side
K4
Unlock Warning Switch
T4
Theft Warning ECU Assy
05-2034
- DIAGNOSTICSTHEFT DETERRENT SYSTEM
2224 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
1 INSPECT UN-LOCK WARNING SWITCH ASSY
(a) Remove the warning switch.
(b) Measure the resistance of the switch.
Standard:
Tester ConnectionConditionSpecified Condition
1 - 2Not pushed
(ON (Key inserted))Below 1 W
1 - 2Pushed
(OFF (Key removed))10 kW or higher
NG REPLACE UN-LOCK WARNING SWITCH ASSY
OK
2 CHECK WIRE HARNESS
(THEFT WARNING ECU ASSY - UNLOCK WARNING SWITCH ASSY)
(a) Disconnect the T4 ECU connector.
(b) Disconnect the K4 switch connector.
(c) Measure the resistance between the wire harness side
connectors.
Standard:
Tester ConnectionSpecified Condition
T4-12 (KSW) - K4-2Below 1 W
NG REPAIR OR REPLACE HARNESS AND
CONNECTOR
OK