
60-1
SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
SUPPLEMENTAL RESTRAINT SYSTEM
6010B-01
PRECAUTION
CAUTION:
S The vehicle is equipped with SRS, which consists of a driver airbag, front passenger airbag,
side airbag and curtain shield airbag. Failure to carry out service operations in the correct se-
quence could cause the SRS to unexpectedly deploy during servicing, possibly leading to a
serious accident. Further, if a mistake is made in servicing the SRS, it is possible that the SRS
may fail to operate when required. Before performing servicing (including removal or installa-
tion of parts, inspection or replacement), be sure to read the following items carefully, then fol-
low the correct procedures indicated in the repair manual.
S Wait at least 90 seconds after the ignition switch is turned to the "LOCK" position and the nega-
tive (-) terminal cable is disconnected from the battery before starting the operation.
(The SRS is equipped with a back-up power source, so that if work is started within 90 seconds
after disconnecting the negative (-) terminal cable of the battery, the SRS may be deployed.)
S Do not expose the horn button assy, instr pnl pass l/door airbag assy, airbag sensor assy cen-
ter, airbag sensor front, front seat airbag assy, side airbag sensor assy, curtain shield airbag
assy, airbag sensor rear, seat position airbag sensor or occupant classification ECU directly
to hot air or flames.
S Be sure to perform the initialization of the occupant classification ECU if any of the following
conditions occur (see page 05-767 ). If the initialization is not performed, the SRS may not oper-
ate properly.
S The occupant classification ECU is replaced.
S Accessories (seatback tray, seat cover, etc.) are installed to the vehicle.
S The passenger seat is removed from the vehicle, and then reinstalled or replaced.
S The passenger airbag ON/OFF indicator light ("OFF") comes on when the passenger seat
is not occupied.
S The vehicle is brought to the workshop for repair due to an accident or collision.
NOTICE:
S Malfunction symptoms of the SRS are difficult to confirm, so DTCs are the most important
source of information when troubleshooting. When troubleshooting the SRS, always inspect
DTCs before disconnecting the battery.
S Even in the case of a minor collision when the SRS does not deploy, the horn button assy, instr
pnl pass l/door airbag assy, airbag sensor assy center, airbag sensor front, front seat airbag
assy, side airbag sensor assy, curtain shield airbag assy, airbag sensor rear, seat position air-
bag sensor and occupant classification ECU should be inspected (see page 60-12 ).
S Before repair work, remove the airbag sensor if any kind of shock is likely to occur to the airbag
sensor during the operation.
S Never use SRS parts from another vehicle. When replacing the parts, replace them with new
ones.
S Never disassemble or repair the horn button assy, instr pnl pass l/door airbag assy, airbag sen-
sor assy center, airbag sensor front, front seat airbag assy, side airbag sensor assy, curtain
shield airbag assy, airbag sensor rear, seat position airbag sensor or occupant classification
ECU in order to reuse it.
S If the horn button assy, instr pnl pass l/door airbag assy, airbag sensor assy center, airbag sen-
sor front, front seat airbag assy, side airbag sensor assy, curtain shield airbag assy, airbag sen-
sor rear, seat position airbag sensor or occupant classification ECU has been dropped, or if
there are any cracks, dents or other defects in the case, bracket or connector, replace it with
a new one.
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 2996
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SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
S Use a volt/ohmmeter with high impedance (10 k/V minimum) for troubleshooting the electrical
circuits.
S Information labels are attached to the periphery of the SRS components. Follow the instruc-
tions in the caution.
S After work on the SRS is completed, perform the SRS warning light check (see page 05-770 ).
S When the negative (-) terminal cable is disconnected from the battery, the memory will be
cleared. Because of this, be sure to make a record of the contents memorized in each system
before starting work. When work is finished, adjust each system as it was before. Never use
a back-up power supply from outside the vehicle to avoid erasing the memory in any system.
S If the vehicle is equipped with a mobile communication system, see page 01-5 .
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 2997
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SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
1. DEPLOYMENT CONDITION
(a) When the vehicle collides and the shock is greater than the specified value, the SRS is activated auto-
matically. The airbag sensor assy center includes the safing sensor and deceleration sensor. The saf-
ing sensor was designed to be turned on at a smaller deceleration rate than the deceleration sensor.
The deceleration sensor determines whether or not ignition is necessary based on signals from the
airbag sensor front. Current flows to the squibs to deploy the SRS when the conditions shown in the
illustrations below are met.
Safing Sensor
ON Horn Button Assy
AND Instr Pnl Pass L/door
Airbag Sensor Deceleration Airbag Assy
Front Sensor ON
H44896
Safing Sensor
ON
AND Front Seat Airbag Assy
Side Airbag
Sensor Assy
H44900
Front Seat Airbag Assy
Deployment
Safing Sensor
Curtain
ON
OR Shield Airbag
AND Assy
Airbag Sensor
Rear
H44901
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 2998
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SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
2. SRS CONNECTORS
HINT:
SRS connectors are located as shown in the following illustration.
13
33
Occupant 19 Curtain Shield Airbag
Classification ECU 20 Assy RH (Rear Squib)
14 34
31
Airbag Sensor Curtain Shield Airbag
9
Rear RH Assy RH (Front Squib)
10 32
29
Side Airbag Front Seat Outer
7
Sensor Assy RH Belt Assy RH (Squib)
8 30
27
Airbag Front Front Seat Airbag
5
RH Sensor Assy RH (Squib)
6
28
25
Instr Pnl Pass
3 L/door Airbag Assy (Squib)
4 26
Airbag Sensor
1
Assy Center 17
2 18
21 23
Spiral Cable Horn Button
3 Sub-assy Assy (Squib)
22 24
4
27
Airbag Sensor Front Seat Airbag
5
Front LH Assy LH (Squib)
6 28
29
Side Airbag Front Seat Outer
7
Sensor Assy LH Belt Assy LH (Squib)
8 30
31
Airbag Sensor Curtain Shield Airbag
9
Rear LH Assy LH (Front Squib)
10 32
11
33
15 Curtain Shield Airbag
Seat Position
Airbag Sensor Assy LH (Rear Squib)
16
12 34
H45346
No. Connector Type Application
Connectors 2, 4, 6, 8, 10, 12, 15, 16, 17, 18, 20*, 21, 25, 27,
(1) Terminal Twin-Lock Mechanism
28
(2) Activation Prevention Mechanism Connectors 2, 4, 22, 24, 26, 28, 30, 32, 34
(3) Electrical Connection Check Mechanism Connectors 1, 2, 3, 4
(4) Half Connection Prevention Mechanism Connectors 6, 8, 10, 18, 21, 25, 27
(5) Connector Lock Mechanism Connectors 23, 29, 31, 33
*: Manual Seat
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 2999
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SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
(a) All connectors in the SRS, except the seat position airbag
sensor connector and the occupant classification ECU
connectors, are colored yellow to distinguish them from
other connectors. These connectors have special func-
tions, and are specially designed for the SRS. All SRS
connectors use durable gold-plated terminals, and are
placed in the locations shown on the previous page to en-
sure high reliability.
Spacer (1) Terminal twin-lock mechanism:
Each connector has a two-piece component con-
Housing sisting of a housing and a spacer. This design en-
ables the terminal to be locked securely by two lock-
ing devices (the retainer and the lance) to prevent
terminals from coming out.
(2) Activation prevention mechanism:
Female Each connector contains a short spring plate. When
Male H45308 the connector is disconnected, the short spring
plate automatically connects the positive (+) termi-
nal and the negative (-) terminal of the squib.
When Connector is Connected When Connector is Disconnected
Short Spring Plate Short Spring Plate
Contacting Male Terminal
Housing
Housing Short Spring Plate ON
Terminal
Squib Squib
Connectors
Short Spring Plate Closed Circuit
H45309
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Author : Date : 3000
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SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
(3) Electrical connection check mechanism:
This mechanism electrically checks that the con-
nectors are connected correctly and completely.
The electrical connection check mechanism is de-
Disconnection
Detection signed so that the disconnection detection pin con-
Pin nects with the diagnosis terminals when the con-
nector housing lock is locked.
Airbag Sensor Assy Center H41646
FHalf Connection FComplete Connection
Terminal for Diagnosis Terminal for
Diagnosis
Disconnection Detection Pin
H01315
(4) Half connection prevention mechanism:
If the connector is not completely connected, the
connector is disconnected due to the spring opera-
tion so that no continuity exists.
Spring
Stopper
Slider Stopper
Locking Part Locking Arm
Rebound by Slider
(Spring)
H44955
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Author : Date : 3001
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SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
(5) Connector lock mechanism:
Locking the connector lock button connects the
connector securely.
1.75
Lock Button
Claw
Groove
H40181
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SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
3. DISCONNECTION OF CONNECTORS FOR HORN BUTTON ASSY AND CURTAIN SHIELD AIR-
BAG ASSY
(a) Release the lock button (yellow part) of the connector using a screwdriver.
(b) Insert the screwdriver tip between the connector and the base, and then raise the connector.
Lock Button Lock Button
(a) (b)
(Yellow Part) (Yellow Part)
H42906
4. CONNECTION OF CONNECTORS FOR HORN BUTTON ASSY AND CURTAIN SHIELD AIRBAG
ASSY
(a) Connect the connector.
(b) Push down securely on the lock button (yellow part) of the connector. (When locking, a click sound can
be heard.)
Lock Button
(Yellow Part)
H43151
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 3003
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SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
5. DISCONNECTION OF CONNECTOR FOR INSTR PNL PASS L/DOOR AIRBAG ASSY
(a) Place a finger on the slider, slide the slider to release the lock, and then disconnect the connector.
Slider Slider
Disconnection is completed
H01586
6. CONNECTION OF CONNECTOR FOR INSTR PNL PASS L/DOOR AIRBAG ASSY
(a) Connect the connector as shown in the illustration. (When locking, make sure that the slider returns
to its original position and a click sound can be heard.)
HINT:
When connecting, the slider will slide. Be sure not to touch the slider while connecting, as it may result in
an insecure fit.
Slider
Slider
Connection is completed
H43731
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Author : Date : 3004
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SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
7. DISCONNECTION OF CONNECTOR FOR FRONT SEAT AIRBAG ASSY
(a) Place a finger on the slider, slide the slider to release the lock, and then disconnect the connector.
Slider Slider
Disconnection is completed
H01584
8. CONNECTION OF CONNECTOR FOR FRONT SEAT AIRBAG ASSY
(a) Connect the connector as shown in the illustration. (When locking, make sure that the slider returns
to its original position and a click sound can be heard.)
HINT:
When connecting, the slider will slide. Be sure not to touch the slider while connecting, as it may result in
an insecure fit.
Slider
Slider
Connection is completed
H43169
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 3005
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SUPPLEMENTAL RESTRAINT SYSTEM - SUPPLEMENTAL RESTRAINT SYSTEM
9. DISCONNECTION OF CONNECTORS FOR AIRBAG
Outer SENSOR FRONT, SIDE AIRBAG SENSOR ASSY AND
AIRBAG SENSOR REAR
(a) While holding both outer flank sides, slide the outer in the
direction shown by the arrow.
(b) When the connector lock is released, the connectors are
disconnected.
HINT:
H02763 Be sure to hold both outer flank sides. Holding the top and bot-
tom will make disconnection difficult.
Connector lock is released
Disconnection is completed
H02764
10. CONNECTION OF CONNECTORS FOR AIRBAG SENSOR FRONT, SIDE AIRBAG SENSOR ASSY
AND AIRBAG SENSOR REAR
(a) Connect the connector as shown in the illustration. (When locking, make sure that the outer returns
to its original position and a click sound can be heard.)
HINT:
When connecting, the outer will slide. Be sure not to hold the outer while connecting, as it may result in an
insecure fit.
Outer Outer
Connection is completed
H02768
2005 SIENNA REPAIR MANUAL (RM1163U)
Author : Date : 3006