Service Manuals, User Guides, Schematic Diagrams or docs for : . Car Manuals Toyota Sienna 2004-2007 Approved SRM 04 05 21q2h73z b1781
<< Back | HomeMost service manuals and schematics are PDF files, so You will need Adobre Acrobat Reader to view : Acrobat Download Some of the files are DjVu format. Readers and resources available here : DjVu Resources
For the compressed files, most common are zip and rar. Please, extract files with Your favorite compression software ( WinZip, WinRAR ... ) before viewing. If a document has multiple parts, You should download all, before extracting.
Good luck. Repair on Your own risk. Make sure You know what You are doing.
Image preview - the first page of the document
>> Download b1781 documenatation <<
Text preview - extract from the document
05-1045
DIAGNOSTICS - SUPPLEMENTAL RESTRAINT SYSTEM 05IWR-04
DTC B1781 OCCUPANT CLASSIFICATION SENSOR
FRONT RH CIRCUIT MALFUNCTION
CIRCUIT DESCRIPTION
The occupant classification sensor front RH circuit consists of the occupant classification ECU and the occu-
pant classification sensor front RH.
DTC B1781 is recorded when a malfunction is detected in the occupant classification sensor front RH circuit.
DTC No. DTC Detecting Condition Trouble Area
S The occupant classification ECU receives a line short circuit
signal, an open circuit signal, a short circuit to ground signal S Seat adjuster frame assy
or a short circuit to B+ signal in the occupant classification (Occupant classification sensor front RH)
B1781
sensor front RH circuit for 2 seconds. S Front seat wire RH
S Occupant classification sensor front RH malfunction S Occupant classification ECU
S Occupant classification ECU malfunction
HINT:
When DTC B1150/23 is detected as a result of troubleshooting for the supplemental restraint system, per-
form troubleshooting for DTC B1781 of the occupant classification system.
WIRING DIAGRAM
O6 Occupant Classification Sensor Front RH Occupant Classification ECU
12
P
O4 SVC2
1
8
LG
O4 SIG2
2
2
B-Y
O4 SGD2
3
H43062
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1228
05-1046
DIAGNOSTICS - SUPPLEMENTAL RESTRAINT SYSTEM
INSPECTION PROCEDURE
HINT:
S 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.
S 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 05-777 ).
HINT:
First clear DTCs stored in the occupant classification ECU and then in the airbag sensor assy center.
(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 05-777 ).
OK:
DTC B1781 is not output.
HINT:
Codes other than code B1781 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 05-770 )
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 occu-
pant classification sensor front RH.
OK:
The connectors are connected.
NG CONNECT CONNECTORS, THEN GO TO STEP
1
OK
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1229
05-1047
DIAGNOSTICS - SUPPLEMENTAL RESTRAINT SYSTEM
3 CHECK FRONT SEAT WIRE RH(TO B+)
Occupant (a) Disconnect the connectors from the occupant classifica-
Occupant tion ECU and the occupant classification sensor front RH.
Classification ECU
Classification
(b) Connect the negative (-) terminal cable to the battery.
Sensor Front RH
(c) Turn the ignition switch to the ON position.
(d) Measure the voltage according to the value(s) in the table
D A below.
C B Standard:
Front Seat
Tester connection Condition Specified condition
Wire RH
O4 O4-2 (SGD2) -
SGD2 Ignition switch ON Below 1 V
Body ground
O4-8 (SIG2) -
Ignition switch ON Below 1 V
Body ground
O4-12 (SVC2) -
SIG2 Ignition switch ON Below 1 V
SVC2 Body ground
H43105
H43111 H43474
NG REPAIR OR REPLACE FRONT SEAT WIRE RH
OK
4 CHECK FRONT SEAT WIRE RH(OPEN)
Occupant Front Seat Wire RH (a) Turn the ignition switch to the LOCK position.
Classification
Occupant (b) Disconnect the negative (-) terminal cable from the bat-
Sensor Front RH tery, and wait for at least 90 seconds.
Classification
ECU (c) Using a service wire, connect O6-1 (SVC2) and O6-3
D A (SGD2), and connect O6-2 (SIG2) and O6-3(SGD2) of
C B connector "C".
NOTICE:
O6 O4
Service Do not forcibly insert a service wire into the terminals of the
Wire SGD2 connector when connecting.
(d) Measure the resistance according to the value(s) in the
SVC2 SGD2 table below.
Standard:
SIG2 Service Tester connection Condition Specified condition
H43106 SIG2 SVC2
H43699 H43111 Wire H43475 O4-8 (SIG2) -
Always Below 1
O4-2 (SGD2)
O4-12 (SVC2) -
Always Below 1
O4-2 (SGD2)
NG REPAIR OR REPLACE FRONT SEAT WIRE RH
OK
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1230
05-1048
DIAGNOSTICS - SUPPLEMENTAL RESTRAINT SYSTEM
5 CHECK FRONT SEAT WIRE RH(SHORT)
(a) Disconnect the service wire from connector "C".
Occupant Front Seat Wire RH (b) Measure the resistance according to the value(s) in the
Classification
Occupant table below.
Sensor Front RH
Classification Standard:
ECU
Tester connection Condition Specified condition
D A O4-8 (SIG2) -
Always 1 M or Higher
C B O4-2 (SGD2)
O4-12 (SVC2) -
Always 1 M or Higher
SGD2 O4 O4-2 (SGD2)
O4-8 (SIG2) -
Always 1 M or Higher
O4-12 (SVC2)
SIG2 SVC2
H43105
H43111 H43474 NG REPAIR OR REPLACE FRONT SEAT WIRE RH
OK
6 CHECK FRONT SEAT WIRE RH(TO GROUND)
(a) Measure the resistance according to the value(s) in the
Occupant Front Seat Wire RH table below.
Classification
Occupant Standard:
Sensor Front RH
Classification Tester connection Condition Specified condition
ECU
O4-2 (SGD2) -
D Always 1 M or Higher
A Body ground
C B O4-8 (SIG2) -
Always 1 M or Higher
Body ground
SGD2 O4 O4-12 (SVC2) -
Always 1 M or Higher
Body ground
SIG2 SVC2
H43105
H43111 H43474 NG REPAIR OR REPLACE FRONT SEAT WIRE RH
OK
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1231
05-1049
DIAGNOSTICS - SUPPLEMENTAL RESTRAINT SYSTEM
7 RECHECK DTC
(a) Connect the connectors to the occupant classification ECU and the occupant classification sensor
front 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 05-777 ).
HINT:
First clear DTCs stored in the occupant classification ECU and then in the airbag sensor assy center.
(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 05-777 ).
OK:
DTC B1781 is not output.
HINT:
Codes other than code B1781 may be output at this time, but they are not related to this check.
NG Go to step 8
OK
USE SIMULATION METHOD TO CHECK (SEE PAGE 05-770 )
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 60-67 ).
HINT:
Perform the inspection using parts from a normal vehicle if possible.
NEXT
9 PERFORM ZERO POINT CALIBRATION
HINT:
Perform the inspection using parts from a normal vehicle if possible.
(a) Using the hand-held tester, perform "Zero point calibration" (see page 05-767 ).
OK:
The "COMPLETED" is displayed.
NG Go to step 12
OK
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1232
05-1050
DIAGNOSTICS - SUPPLEMENTAL RESTRAINT SYSTEM
10 PERFORM SENSITIVITY CHECK
(a) Using the hand-held tester, perform "Sensitivity check" (see page 05-767 ).
Standard value: 27 to 33 kg (59.52 to 72.75 lb)
NG Go to step 12
OK
11 RECHECK DTC
(a) Connect the negative (-) terminal cable to the battery.
(b) Turn the ignition switch to the ON position.
(c) Clear the DTCs stored in memory (see page 05-777 ).
HINT:
First clear DTCs stored in the occupant classification ECU and then in the airbag sensor assy center.
(d) Turn the ignition switch to the LOCK position.
(e) Turn the ignition switch to the ON position.
(f) Using the hand-held tester, check the DTCs (see page 05-777 ).
OK:
DTC B1781 is not output.
HINT:
Codes other than code B1781 may be output at this time, but they are not related to this check.
NG Go to step 12
OK
END
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1233
05-1051
DIAGNOSTICS - SUPPLEMENTAL RESTRAINT SYSTEM
12 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 72-30 ).
NEXT
13 PERFORM ZERO POINT CALIBRATION
(a) Connect the negative (-) terminal cable to the battery.
(b) Connect the hand-held tester to the DLC3.
(c) Turn the ignition switch to the ON position.
(d) Using the hand-held tester, perform "Zero point calibration" (see page 05-767 ).
OK:
The "COMPLETED" is displayed.
NEXT
14 PERFORM SENSITIVITY CHECK
(a) Using the hand-held tester, perform "Sensitivity check" (see page 05-767 ).
Standard value: 27 to 33 kg (59.52 to 72.75 lb)
NEXT
END
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 1234
◦ Jabse Service Manual Search 2026 ◦ Jabse Pravopis ◦ onTap.bg ◦ Other service manual resources online : Fixya ◦ eServiceinfo