TOYOTA SEQUOIA 2001 Service Repair Manual

SR±56
± STEERINGPOWER STEERING GEAR
3283 Author: Date:
2005 SEQUOIA (RM1146U)
12. TORQUE STEERING WHEEL SET NUT
Torque: 50 N´m (510 kgf´cm, 37 ft´lbf)
13. INSTALL STEERING WHEEL PAD (See page SR±23)
14. CHECK FRONT WHEEL ALIGNMENT
(See page SA±4)
15. CONNECT CABLE TO NEGATIVE BATTERY TERMI-
NAL
16. PERFORM YAW RATE AND DECELERATION SENSOR
ZERO POINT CALIBRATION (See page DI±897)
17. PERFORM INITIALIZATION (See page IN±20)
Some systems need initialization when disconnecting the cable
from the negative battery terminal.

RS0B6±09
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS±1
3284 Author: Date:
2005 SEQUOIA (RM1146U)
SRS AIRBAG
PRECAUTION
CAUTION:

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.

Wait at least 90 seconds after the ignition switch is turned to the ºLOCKº position and the nega-
tive (±) terminal cable is disconnected from the battery.
(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.)

Do not expose the steering wheel pad, front passenger airbag assembly, side airbag assembly,
curtain shield airbag assembly, airbag sensor assembly, front airbag sensor, side airbag sen-
sor assembly, curtain shield airbag sensor assembly, seat position sensor assembly or occu-
pant classification ECU directly to hot air or flames.

Be sure to perform the initialization of the occupant classification ECU if any of the following
conditions occur (see page DI±1128). If the initialization is not performed, the SRS may not oper-
ate 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.
NOTICE:

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.

Even in the case of a minor collision when the SRS does not deploy, the steering wheel pad,
front passenger airbag assembly, side airbag assembly, curtain shield airbag assembly, airbag
sensor assembly, front airbag sensor, side airbag sensor assembly, curtain shield airbag sen-
sor assembly, seat position sensor assembly and occupant classification ECU should be in-
spected. (see page RS±22, RS±35, RS±49, RS±64, RS±72, RS±83, RS±88, RS±93, RS±98,
RS±106 and RS±112).

Before repair work, remove the airbag sensor if any kind of shock is likely to occur to the airbag
sensor during the operation.

Never use SRS parts from another vehicle. When replacing the parts, replace them with new
ones.

Never disassemble or repair the steering wheel pad, front passenger airbag assembly, side air-
bag assembly, curtain shield airbag assembly, airbag sensor assembly, front airbag sensor,
side airbag sensor assembly, curtain shield airbag sensor assembly, seat position sensor as-
sembly or occupant classification ECU in order to reuse it.

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.

H23941
RS±6
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
3289 Author: Date:
2005 SEQUOIA (RM1146U)
14. RSCA OFF SWITCH
The RSCA OFF switch is located on the switch base. The cur-
tain shield airbag can be switched ON and OFF by pushing the
RCSA OFF switch. Also, the RCSA OFF indicator lamp comes
on to inform the passenger that the curtain shield airbag is dis-
abled.
Switch PositionCurtain Shield AirbagIndicator Light
ONOperativeOFF
OFFDisabledON

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.

C51019H20054
Stopper
Locking PartSpring
Slider
Locking Arm
Rebounded by Slider
(Spring)Stopper
H20055
Claw
GrooveLock Button
± SUPPLEMENTAL RESTRAINT SYSTEMSRS AIRBAG
RS±9
3292 Author: Date:
2005 SEQUOIA (RM1146U)
(3) Half connection prevention mechanism:
If the connector is not completely connected, the
connector is disconnected due to the spring opera-
tion to the extent that no continuity exists.
(4) Connector lock mechanism (1):
Locking the connector lock button securely con-
nects the connector.