TOYOTA HIGHLANDER 2001 Service Repair Manual

05-1488
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1678 Author
: Date
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
3 CHECK DTC
(a) Turn the ignition switch to the ON position.
(b) Clear the DTCs stored in airbag sensor assy center memory (see page 05-1215).
(c) Turn the ignition switch to the LOCK position.
(d) Turn the ignition switch to the ON position.
(e) Using the hand-held tester, check the DTCs (see page 05-1215).
OK:
DTC B1787 is not output.
HINT:
Codes other than code B1787 may be output at this time, but they are not related to this check.
NG Go to step 4
OK
END
4 REPLACE SEAT ADJUSTER FRAME ASSY
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Replace the seat adjuster frame assy (see page 72-1 1, 72-19).
HINT:
Perform the inspection using parts from a normal vehicle when possible.
5 PERFORM ZERO POINT CALIBRATION
(a) Using the hand-held tester, perform ºZero point calibrationº (see page 05-1203).
OK:
The ºCOMPLETEDº is displayed.
NG Go to step 8
OK
6 PERFORM SENSITIVITY CHECK
(a) Using the hand-held tester, perform ºSensitivity checkº (see page 05-1203).
Standard value: 27 to 33 kg (59.52 to 72.75 lb)
NG Go to step 8
OK

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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
7 CHECK DTC
(a) Connect the connectors to the occupant classification ECU and the occupant classification sensor rear
LH.
(b) Connect the negative (-) terminal cable to the battery.
(c) Turn the ignition switch to the ON position.
(d) Clear the DTCs stored in memory (see page 05-1215).
HINT:

First clear DTCs stored in the occupant classification ECU memory and then in the airbag sensor assy
center memory.

Use the hand-held tester to clear the DTC of the occupant classification ECU, otherwise the DTC can-
not be cleared.
(e) Turn the ignition switch to the LOCK position.
(f) Turn the ignition switch to the ON position.
(g) Using the hand-held tester, check the DTCs (see page 05-1215).
OK:
DTC B1787 is not output.
HINT:
Codes other than code B1787 may be output at this time, but they are not related to this check.
NG Go to step 8
OK
END
8 REPLACE OCCUPANT CLASSIFICATION ECU
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Replace the occupant classification ECU (see page 60-64).
9 PERFORM ZERO POINT CALIBRATION
(a) Using the hand-held tester, perform ºZero point calibrationº (see page 05-1203).
OK:
The ºCOMPLETEDº is displayed.
10 PERFORM SENSITIVITY CHECK
(a) Using the hand-held tester, perform ºSensitivity checkº (see page 05-1203).
Standard value: 27 to 33 kg (59.52 to 72.75 lb)
END

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1680 Author
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
DTC B1788 OCCUPANT CLASSIFICATION SENSOR
REAR RH COLLISION DETECTION
CIRCUIT DESCRIPTION
DTC B1788 is output when the occupant classification ECU receives a collision detection signal sent by the
occupant classification sensor rear RH if an accident occurs.
DTC B1788 is also output when the seat adjuster frame assy is subjected to a strong impact, even if an actual
accident does not occur.
However, when the occupant classification ECU outputs a collision detection signal, even if the vehicle is
not in a collision, DTC B1788 can be cleared by ºZero point calibrationº and ºSensitivity checkº.
Therefore, if DTC B1788 is output, first perform ºZero point calibrationº and ºSensitivity checkº.
DTC No.DTC Detecting ConditionTrouble Area
B1788

Seat adjuster frame assy malfunction

Occupant classification ECU malfunction

Occupant classification sensor rear RH sensed large load
Occupant classification ECU

Seat adjuster frame assy
(Occupant classification sensor rear RH)
HINT:

When DTC B1150/23 is detected as a result of troubleshooting for the supplemental restraint system,
perform troubleshooting for DTC B1788 of the classification system.

Use the hand-held tester to check the DTC of the occupant classification ECU, otherwise the DTC
cannot be read.
WIRING DIAGRAM
see page 05-1474.
INSPECTION PROCEDURE
1 PERFORM ZERO POINT CALIBRATION
(a) Using the hand-held tester, perform ºZero point calibrationº (see page 05-1203).
OK:
The ºCOMPLETEDº is displayed.
NG Go to step 4
OK
2 PERFORM SENSITIVITY CHECK
(a) Using the hand-held tester, perform ºSensitivity checkº (see page 05-1203).
Standard value: 27 to 33 kg (59.52 to 72.75 lb)
NG Go to step 4
OK
05IWY-01

- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
3 CHECK DTC
(a) Turn the ignition switch to the ON position.
(b) Clear the DTCs stored in airbag sensor assy center memory (see page 05-1215).
(c) Turn the ignition switch to the LOCK position.
(d) Turn the ignition switch to the ON position.
(e) Using the hand-held tester, check the DTCs (see page 05-1215).
OK:
DTC B1788 is not output.
HINT:
Codes other than code B1788 may be output at this time, but they are not related to this check.
NG Go to step 4
OK
END
4 REPLACE SEAT ADJUSTER FRAME ASSY
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Replace the seat adjuster frame assy (see page 72-1 1, 72-19).
HINT:
Perform the inspection using parts from a normal vehicle when possible.
5 PERFORM ZERO POINT CALIBRATION
(a) Using the hand-held tester, perform ºZero point calibrationº (see page 05-1203).
OK:
The ºCOMPLETEDº is displayed.
NG Go to step 8
OK
6 PERFORM SENSITIVITY CHECK
(a) Using the hand-held tester, perform ºSensitivity checkº (see page 05-1203).
Standard value: 27 to 33 kg (59.52 to 72.75 lb)
NG Go to step 8
OK

05-1492
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
1682 Author
: Date
:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
7 CHECK DTC
(a) Connect the connectors to the occupant classification ECU and the occupant classification sensor rear
RH.
(b) Connect the negative (-) terminal cable to the battery.
(c) Turn the ignition switch to the ON position.
(d) Clear the DTCs stored in memory (see page 05-1215).
HINT:

First clear DTCs stored in the occupant classification ECU memory and then in the airbag sensor assy
center memory.

Use the hand-held tester to clear the DTC of the occupant classification ECU, otherwise the DTC can-
not be cleared.
(e) Turn the ignition switch to the LOCK position.
(f) Turn the ignition switch to the ON position.
(g) Using the hand-held tester, check the DTCs (see page 05-1215).
OK:
DTC B1788 is not output.
HINT:
Codes other than code B1788 may be output at this time, but they are not related to this check.
NG Go to step 8
OK
END
8 REPLACE OCCUPANT CLASSIFICATION ECU
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Replace the occupant classification ECU (see page 60-64).
9 PERFORM ZERO POINT CALIBRATION
(a) Using the hand-held tester, perform ºZero point calibrationº (see page 05-1203).
OK:
The ºCOMPLETEDº is displayed.
10 PERFORM SENSITIVITY CHECK
(a) Using the hand-held tester, perform ºSensitivity checkº (see page 05-1203).
Standard value: 27 to 33 kg (59.52 to 72.75 lb)
END

- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
05-1493
1683 Author
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
DTC B1790 AIRBAG SENSOR ASSY CENTER
COMMUNICATION CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
The airbag sensor assy center communication circuit consists of the occupant classification ECU and the
airbag sensor assy center.
DTC B1790 is recorded when a malfunction is detected in the airbag sensor assy center communication
circuit.
DTC No.DTC Detecting ConditionTrouble Area
B1790

When the occupant classification ECU receives a line
short signal, open signal, short to ground signal or B+
short signal in the airbag sensor assy center communica-
tion circuit for 2 seconds.

Airbag sensor assy center malfunction

Occupant classification ECU malfunction

Occupant classification ECU

Airbag sensor assy center

Floor wire

Front seat wire RH
HINT:

When DTC B1150/23 is detected as a result of troubleshooting for the supplemental restraint system,
perform troubleshooting for DTC B1790 of the occupant classification system.

Use the hand-held tester to check the DTC of the occupant classification ECU, otherwise the DTC
cannot be read.
05IX3-02

H43055H44108
Airbag Sensor Assy Center Occupant Classification ECU
FSR+
FSR- FSR+
FSR-813
410
4 WW
BB
BL1 O6
O6A18
A18 BL1
A18
A18(*1)
(*1) (*2) (*2)1
2
*1: w/ Curtain Shield Airbag
*2: w/o Curtain Shield Airbag 05-1494
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
WIRING DIAGRAM

- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
05-1495
1685 Author
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
HINT:

If troubleshooting (wire harness inspection) is difficult to perform, remove the front RH seat assy instal-
lation bolts to see the under surface of seat cushion.

In the above case, hold the seat so that it does not fall down. Holding the seat for a long period of time
may cause a problem, such as seat rail deformation. Hold the seat only as necessary.
1 CHECK DTC
(a) Turn the ignition switch to the ON position.
(b) Clear the DTCs stored in memory (see page 05-1215).
HINT:

First clear DTCs stored in the occupant classification ECU memory and then in the airbag sensor assy
center memory.

Use the hand-held tester to clear the DTC of the occupant classification ECU, otherwise the DTC can-
not be cleared.
(c) Turn the ignition switch to the LOCK position.
(d) Turn the ignition switch to the ON position.
(e) Using the hand-held tester, check the DTCs (see page 05-1215).
OK:
DTC B1790 is not output.
HINT:
Codes other than code B1790 may be output at this time, but they are not related to this check.
NG Go to step 2
OK
USE SIMULATION METHOD TO CHECK (SEE PAGE 05-1207)
2 CHECK CONNECTION OF CONNECTORS
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Check that the connectors are properly connected to the occupant classification ECU and the airbag
sensor assy center.
OK:
The connectors are connected.
NG CONNECT CONNECTORS, THEN GO TO STEP
1
OK

H41715H44130H44536
Occupant
Classification ECU
FAirbag
Sensor
Assy
Center A
FSR-
FSR+ EDCB
A18
FSR-FSR+
A18
w/ Side and Curtain
Shield Airbagw/o Side and Curtain
Shield Airbag
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
3 PREPARE FOR INSPECTION
CAUTION:
Be sure to perform the following procedures before troubleshooting to avoid unexpected airbag de-
ployment.
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
(c) Disconnect the connectors from the airbag sensor assy center.
(d) Disconnect the connectors from the horn button assy.
(e) Disconnect the connectors from the front passenger airbag assy.
(f) Disconnect the connector from the front seat airbag assy LH
(g) Disconnect the connector from the front seat airbag assy RH.
(h) Disconnect the connector from the curtain shield airbag assy LH.
(i) Disconnect the connector from the curtain shield airbag assy RH
(j) Disconnect the connector from the front seat outer belt assy LH.
(k) Disconnect the connector from the front seat outer belt assy RH.
4 CHECK WIRE HARNESS (TO B+)
(a) Disconnect the connector from the occupant classifica-
tion ECU.
(b) Connect the negative (-) terminal cable to the battery.
(c) Turn the ignition switch to the ON position.
(d) Measure the voltage according to the value(s) in the table
below.
Standard:
w/ Side and curtain shield airbag:
Tester connectionConditionSpecified condition
A18-3 (FSR+) -
Body groundIgnition switch ONBelow 1 V
A18-10 (FSR-) -
Body groundIgnition switch ONBelow 1 V
w/o Side and curtain shield airbag:
Tester connectionConditionSpecified condition
A18-1 (FSR+) -
Body groundIgnition switch ONBelow 1 V
A18-2 (FSR-) -
Body groundIgnition switch ONBelow 1 V
NG Go to step 13
OK

H41715H44130 H44536H43694H44681
Occupant
Classification ECUAirbag
Sensor
Assy
Center
FSR+ F
CBA
ED
FSR-
FSR-FSR+
Service Wire
O6
A18 A18
(*1) (*2) FSR-
FSR+
*1: w/ Side and Curtain Shield Airbag
*2: w/o Side and Curtain Shield Airbag
H41715H44130H44536
Occupant
Classification ECU
FAirbag
Sensor
Assy
Center A
FSR-
FSR+ EDCB
A18
FSR-FSR+
A18
w/ Side and Curtain
Shield Airbagw/o Side and Curtain
Shield Airbag
- DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
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2005 HIGHLANDER REPAIR MANUAL (RM1144U)
5 CHECK WIRE HARNESS (OPEN)
(a) Turn the ignition switch to the LOCK position.
(b) Disconnect the negative (-) terminal cable from the bat-
tery, and wait for at least 90 seconds.
(c) Using a service wire, connect the O6-8 (FSR+) and O6-4
(FSR-) of connector ºEº.
NOTICE:
Do not forcibly insert a service wire into the terminal of the
connector when connecting.
(d) Measure the resistance according to the value(s) in the
table below.
Standard:
w/ Side and curtain shield airbag:
Tester connectionConditionSpecified condition
A18-3 (FSR+) -
A18-10 (FSR-)AlwaysBelow 1 W
w/o Side and curtain shield airbag:
Tester connectionConditionSpecified condition
A18-1 (FSR+) -
A18-2 (FSR-)AlwaysBelow 1 W
NG Go to step 14
OK
6 CHECK WIRE HARNESS (SHORT)
(a) Disconnect the service wire from connector ºEº.
(b) Measure the resistance according to the value(s) in the
table below.
w/ Side and curtain shield airbag:
Tester connectionConditionSpecified condition
A18-3 (FSR+) -
A18-10 (FSR-)Always1 MW or Higher
w/o Side and curtain shield airbag:
Tester connectionConditionSpecified condition
A18-1 (FSR+) -
A18-2 (FSR-)Always1 MW or Higher
NG Go to step 15
OK