sensor TOYOTA SEQUOIA 2001 Service Repair Manual

RS±2
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
3285 Author: Date:
2005 SEQUOIA (RM1146U)

If the steering wheel pad, front passenger airbag assembly, side airbag assembly, curtain
shield airbag assembly, airbag sensor assembly, front airbag sensor, side airbag sensor as-
sembly, curtain shield airbag sensor assembly, seat position sensor assembly 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.

Use a volt/ohmmeter with high impedance (10 kW/V minimum) for troubleshooting the electrical
circuits.

Information labels are attached to the periphery of the SRS components. Follow the instruc-
tions in the caution.

After work on the SRS is completed, perform the SRS warning light check (see page DI±1137).

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.

RS116±01
H24695
H23918Spiral Cable
H16182
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS±3
3286 Author: Date:
2005 SEQUOIA (RM1146U)
OPERATION
CAUTION:
Be sure to perform the initialization of the occupant classi-
fication ECU if any of the following conditions occur (see
page DI±1128). If the initialization is not performed, the SRS
may not operate properly.

The occupant classification ECU is replaced.

Accessories (seatback tray, seat cover, etc.) are
installed to the vehicle.

The passenger seat is removed from the vehicle, and
then reinstalled or replaced.

The passenger airbag ON/OFF indicator light (ºOFFº)
comes on when the passenger seat is not occupied.

The vehicle is brought to the workshop for repair due
to an accident or collision.
1. STEERING WHEEL PAD
The inflator and bag of the SRS are stored in the steering wheel
pad and cannot be disassembled. The inflator contains a squib,
igniter charge, and gas generator, etc., and inflates the bag
when instructed by the airbag sensor assembly. The steering
wheel pad cannot be disassembled.
2. SPIRAL CABLE
A spiral cable is used as an electrical joint from the vehicle body
side to the steering wheel. The spiral cable cannot be disas-
sembled.
3. FRONT PASSENGER AIRBAG ASSEMBLY
The inflator and bag of the SRS are stored in the front passen-
ger airbag assembly and cannot be disassembled. The inflator
contains a squib, igniter charge, gas generator, etc., and in-
flates the bag when instructed by the airbag sensor assembly.
The front passenger airbag assembly cannot be disassembled.

H17489
H23919
H16185
H23920
H16187
RS±4
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
3287 Author: Date:
2005 SEQUOIA (RM1146U)
4. SIDE AIRBAG ASSEMBLY
The inflator and bag of the SRS are stored in the side airbag as-
sembly and cannot be disassembled. The inflator contains a
squib, igniter charge and gas generator, etc., and inflates the
bag when instructed by the airbag sensor assembly. The side
airbag assembly cannot be disassembled.
5. CURTAIN SHIELD AIRBAG ASSEMBLY
The inflator and bag of the SRS are stored in the curtain shield
airbag assembly and cannot be disassembled. The inflator con-
tains a squib, igniter charge, gas generator, etc., and inflates
the bag when instructed by the airbag sensor assembly. The
curtain shield airbag assembly cannot be disassembled.
6. SEAT BELT PRETENSIONER
The front seat outer belt has the seat belt pretensioner system.
The pretensioner operates in the event of a frontal collision. The
seat belt pretensioner cannot be disassembled.
7. SRS WARNING LIGHT
The SRS warning light is located on the combination meter. It
comes on to alert the driver of trouble in the system when a mal-
function is detected in the airbag sensor assembly. In normal
operation conditions when the ignition switch is turned to the
ON position, the light comes on for approximately 6 seconds
and then goes off.
8. AIRBAG SENSOR ASSEMBLY
The airbag sensor assembly is mounted on the floor inside the
lower center finish panel. The airbag sensor assembly consists
of an airbag sensor, safing sensor, diagnosis circuit, ignition
control, drive circuit, etc. It receives signals from the airbag sen-
sor, front airbag sensor, side and curtain shield airbag sensor
and curtain shield airbag sensor, and judges whether the SRS
must be activated or not. The airbag sensor assembly cannot
be disassembled.

H23921
H20065
H23922
H23923
H23924
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS±5
3288 Author: Date:
2005 SEQUOIA (RM1146U)
9. FRONT AIRBAG SENSOR
The front airbag sensor is mounted inside each of the radiator
support. The front airbag sensor consists of an airbag sensor,
diagnosis circuit, etc. It sends signals to the airbag sensor as-
sembly to judge whether the SRS must be activated or not. The
front airbag sensor cannot be disassembled.
10. SIDE AIRBAG SENSOR ASSEMBLY
The side airbag sensor assembly is mounted in the LH and RH
center pillars. The side airbag sensor assembly consists of an
airbag sensor, diagnosis circuit, etc. It sends signals to the air-
bag sensor assembly to judge whether the SRS must be acti-
vated or not. The side airbag sensor assembly cannot be disas-
sembled.
11. CURTAIN SHIELD AIRBAG SENSOR ASSEMBLY
The curtain shield airbag sensor assembly is mounted in the LH
and RH quarter panels. The curtain shield airbag sensor as-
sembly consists of an airbag sensor, diagnosis circuit, etc. It
sends signals to the airbag sensor assembly to judge whether
the SRS must be activated or not. The curtain shield airbag sen-
sor assembly cannot be disassembled.
12. SEAT POSITION SENSOR ASSEMBLY
The seat position sensor assembly is mounted in the driver's
seat. The sensor unit consists of a magnet sensor, etc. It judges
the seat sliding position and sends the signal to the airbag sen-
sor assembly. The seat position sensor assembly cannot be
disassembled.
13. OCCUPANT CLASSIFICATION ECU
The occupant classification ECU is mounted in the passenger
seat. Based on the information sent from the occupant classifi-
cation ECU, the airbag sensor assembly determines whether
the SRS should be activated or not. The occupant classification
ECU cannot be disassembled.

H23944
Side Airbag
Sensor Assembly RH (*1)
Airbag Sensor
AssemblyFront Seat Outer
Belt Assembly RH
Front Seat Airbag
Assembly RH (Squib) (*1) 14 13
Front Airbag Sensor
LH
Side Airbag
Sensor Assembly LH (*1)
Seat Position
Airbag SensorFront Seat Airbag
Assembly LH (Squib)
Curtain Shield Airbag
Assembly LH (Squib) (*1) Front Airbag Sensor
RHFront Passenger
Airbag Assembly (Squib)
Front Seat Outer
Belt Assembly LH (*1)
Spiral Cable
Curtain Shield Airbag
Assembly RH (Squib) (*1)
10 9
8 7
6 5
4 3
2 1
4 3
6 5
8 7
10 9
12 1116 15
18 17
18 17
20 1922 2132 31
30 29
28 27
26 25
34 33
36 35
28 27
30 29
32 3124 23 Occupant
Classification ECU
Curtain Shield Airbag
Sensor Assembly RH (*1)
Curtain Shield Airbag
Sensor Assembly LH (*1)Steering Wheel
Pad (Squib) RCSA OFF Switch (*1) RCSA OFF Switch
(Light) (*1)
(*1) w/ Side Airbag and Curtain Shield Airbag
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS±7
3290 Author: Date:
2005 SEQUOIA (RM1146U)
15. SRS CONNECTORS
HINT:
SRS connectors are located as shown in the following illustration.
No.Connector TypeApplication
(1)Terminal Twin±Lock MechanismConnectors 2, 4, 6, 8, 10, 18, 21, 25, 26, 27, 28
(2)Activation Prevention MechanismConnectors 2, 4, 22, 24, 26, 28, 30, 32
(3)Half Connection Prevention MechanismConnectors 6, 8, 10, 17, 21, 25, 27
(4)Connector Lock Mechanism (1)Connectors 23, 29, 31
(5)Connector Lock Mechanism (2)Connectors 2, 4
(6)Improper Connection Prevention Lock MechanismConnectors 1, 3

Z05953
Spacer
Housing
Female Male
R10587
When Connector is Connected When Connector is Disconnected
Short Spring Plate
Housing
Housing
Terminal
ConnectorsShort Spring PlateSquib
Closed CircuitSquib Short Spring Plate ONContacting Male Terminal Short Spring Plate
RS±8
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
3291 Author: Date:
2005 SEQUOIA (RM1146U)
(a) All connectors in the SRS, except the seat position airbag
sensor connector and occupant classification ECU con-
nectors, are colored yellow to distinguish them from other
connectors. These connectors have special functions,
and are specially designed for the SRS. All SRS connec-
tors use durable gold±plated terminals, and are placed in
the locations shown on the previous page to ensure high
reliability.
(1) Terminal Twin±Lock Mechanism
Each connector has a two±piece component con-
sisting of a housing and a spacer. This design al-
lows 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
Each connector contains a short spring plate. When
the connector is disconnected, the short spring
plate automatically connects the positive (+) termi-
nal and negative (±) terminal of the squib.

H23909
A
Disconnection is completed Holder (with connectors)
H23910
Retainer
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS±13
3296 Author: Date:
2005 SEQUOIA (RM1146U)
20. DISCONNECTION OF CONNECTOR FOR AIRBAG SENSOR ASSY CENTER
(a) Pull the lever by pushing part A as shown in the illustration and disconnect the holder (with connectors).
HINT:
Perform the following procedures when replacing the holder.
(b) Remove the holder.
(1) Using a screwdriver, unlock the retainer.

H23913
Connection is completed Lever
Holder (with connectors)
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS±15
3298 Author: Date:
2005 SEQUOIA (RM1146U)
21. CONNECTION OF CONNECTOR FOR AIRBAG SENSOR ASSY CENTER
(a) Firmly insert the holder (with connectors) until it can not be pushed any further.
(b) Push the lever to connect the holder (with connectors). (When locking, a click sound can be heard.)
HINT:
The holder slides when connecting. Be sure not to hold the holder while connecting, as it may result in an
insecure fit.

H24685
Housing Lock (White Part) A
CPA (Yellow Part)
Connector
lock is
released
H24686
RS±16
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
3299 Author: Date:
2005 SEQUOIA (RM1146U)
22. DISCONNECTION OF CONNECTOR FOR FRONT AIRBAG SENSOR
(a) Push down the housing lock (white part) and slide the CPA (yellow part). (At this time, the connector
cannot be disconnected yet).
(b) Push down the housing lock (white part) again and disconnect the connector.
HINT:
Do not push down the A part shown in the illustration when disconnecting.
(c) After disconnecting the connector, check that the position of the housing lock (the white part) is as
shown in the illustration.

H24687
H24688
Housing Lock
(White Part) A
CPA (Yellow Part)
Connection is
completed
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS±17
3300 Author: Date:
2005 SEQUOIA (RM1146U)
23. CONNECTION OF CONNECTOR FOR FRONT AIRBAG SENSOR
(a) Before connecting the connectors, check that the position of the housing lock (the white part) is as
shown in the illustration.
(b) Be sure to engage the connectors until they are locked. (When locking, make sure that a click sound
can be heard.)
HINT:
When connecting them, the housing lock (white part) slides. Be sure not to hold the housing lock (white part)
and A part, as it may result in an insecure fit.