ignition switch LEXUS SC400 1991 Service Repair Manual

OPERATION
FUNCTION OF COMPONENTS
RS02M±04
1. STEERING WHEEL PAD (with AIRBAG)The inflater and bag of the supplemental restraint system are
stored in the steering wheel pad and cannot be disas-
sembled. The inflater contains a squib, igniter charge, gas
generant, etc., and inflates the bag in case of frontal collision.
2. SPIRAL CABLE (in COMBINATION SWITCH) A spiral cable is used as an electrical joint from the vehicle
body side to the steering wheel.
3. FRONT PASSENGER AIRBAG ASSEMBLY The inflater and bag of the supplemental restraint system are
stored in the front passenger airbag assembly and cannot be
disassembled.
The inflater contains a squib, igniter charge, gas generant,
etc., and inflates the bag in case of a frontal collision.
4. SRS WARNING LIGHT The SRS warning light is located on the combination meter.
It goes on to alert the driver of trouble in the system when a
malfunction is detected in the center airbag sensor assembly.
In normal operating conditions when the ignition switch is
turned to the ACC or ON position, the light goes on for about
6 seconds and then goes off.
5. FRONT AIRBAG SENSOR A front airbag sensor is mounted inside each of the front fend-
ers. The sensor unit is a mechanical type. When the sensor
detects deceleration force above a predetermined limit, con-
tacts is m ade in the sensor, sending a signal to the center air-
bag sensor assembly. The sensor cannot be disassembled.
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SUPPLEMENTAL RESTRAINT SYSTEM OPERATIONRS±9
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COMPONENTS
RS04D±01
STEERING WHEEL PAD AND SPIRAL
CABLE REMOVAL AND INSTALLATION
RS04D±01
NOTICE:
wIf the wiring connector of the supplemental restraint
system is disconnected with the ignition switch at ON or
ACC, diagnostic trouble codes will be recorded.
w Never use SRS parts from another vehicle. When
replacing parts, replace with new parts.
1. DISCONNECT NEGATIVE (±) TERMINAL CABLE FROM
BATTERY
CAUTION: Work must be started after 90 seconds from
the time the ignition switch is turned to the LOCK posi-
tion and the negative (±) terminal cable is disconnected
from the battery (See page RS±2).
RS±18
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SUPPLEMENTAL RESTRAINT SYSTEM STEERING WHEEL PAD AND SPIRAL CABLE
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When scrapping vehicle
HINT: Have a battery ready as the power source to deploy the
airbag.
1. DISCONNECT NEGATIVE (±) TERMINAL CABLE FROM BATTERY
CAUTION: Work must be started after 90 seconds from
the time the ignition switch is turned to the LOCK posi-
tion and the negative (±) terminal cable is disconnected
from the battery (See page RS±2).
2. CONFIRM FUNCTIONING OF SST (See page RS±27)
SST 09082±00700
3. INSTALL SST CAUTION: Check that there is no looseness in the steer-
ing wheel and steering wheel pad.
(a) Remove the No.1 under cover.
(b) Disconnect the airbag connector of the spiral cable.
(c) Connect the SST connector to the airbag connector of the spiral cable.
SST 09082±00700
(d) Move the SST to at least 10 m (33 ft) from the front of the vehicle.
(e) Close all the doors and windows of the vehicle. NOTICE: Take care not to damage the SST wire harness.
(f) Connect the SST red clip to the battery positive (+) terminal and the black clip to the battery negative (±) terminal.
RS±22±
SUPPLEMENTAL RESTRAINT SYSTEM STEERING WHEEL PAD AND SPIRAL CABLE
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4. DEPLOY AIRBAG
(a) Confirm that no±one is inside the vehicle or within 10 m (33ft) of the vehicle.
(b) Press the SST activation switch and deploy the airbag. HINT: The airbag deploys simultaneously as the LED of the
SST activation switch lights up.
5. DISPOSAL OF STEERING WHEEL PAD (WITH AIRBAG)
CAUTION:
w The steering wheel pad is very hot when the airbag is
deployed, so leave it alone for at least 30 minutes after
deployment.
w Use gloves and safety glasses when handling a steering
wheel pad with deployed airbag.
w Do not apply water, etc. to a steering wheel pad with
deployed airbag.
w Always wash your hands with water after completing the
operation.
(a) When scrapping a vehicle, deploy the airbag and scrap the
vehicle with the steering wheel pad still installed.
(b) When moving a vehicle for scrapping which has a steering
wheel pad with deployed airbag, use gloves and safety
glasses.
When disposing of the steering wheel
pad only
When disposing of the steering wheel pad (with airbag)
only, never use the customer's vehicle to deploy the air-
bag.
Remove the steering wheel pad from the vehicle and be sure
to follow the procedure given below when deploying the air-
bag.
HINT: Have a battery ready as the power source deploy the
airbag.
1. REMOVE STEERING WHEEL PAD (See page RS±18)
CAUTION:
w When removing the steering wheel pad (with airbag),
work must be started after 90 seconds from the time the
ignition switch is turned to the LOCK position and the
negative (±) terminal cable is disconnected from the
battery.
w When storing the steering wheel pad, keep the upper
surface of the pad facing upward.
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SUPPLEMENTAL RESTRAINT SYSTEM STEERING WHEEL PAD AND SPIRAL CABLERS±23
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COMPONENTS
RS043±01
FRONT PASSENGER AIRBAG
ASSEMBLY REMOVAL AND
INSTALLATION
RS044±01
NOTICE:
wIf the wiring connector of the supplemental restraint
system is disconnected with the ignition switch at ON or
ACC, diagnostic trouble codes will be recorded.
w Never use airbag parts from another vehicle. When
replacing parts, replace with new parts.
RS±30±
SUPPLEMENTAL RESTRAINT SYSTEM FRONT PASSENGER AIRBAG ASSEMBLY
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1. DISCONNECT NEGATIVE (±) TERMINAL CABLE FROMBATTERY
CAUTION: Work must be started after 90 second from the
time the ignition switch is turned to the LOCK position
and the negative (±) terminal cable is disconnected from
the battery (See page RS±2).
2. REMOVE NO. 2 INSTRUMENT PANEL UNDER COVER
(a) Using a clip remover, remove 2 clips.
(b) Remove the under cover.
3. DISCONNECT AIRBAG CONNECTER
(a) Remove the glove compartment door finish plate inside the glove compartment.
NOTICE: When handling the airbag connector, take care
not to damage the airbag wire harness.
(b) Pull up the connector.
(c) Disconnect the airbag connector.
4. REMOVE GLOVE COMPARTMENT ASSEMBLY
(a) Remove the 2 console box hole covers.
(b) Remove the 4 screws and clip.
(c) Remove the glove compartment assembly.
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SUPPLEMENTAL RESTRAINT SYSTEM FRONT PASSENGER AIRBAG ASSEMBLYRS±31
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When scrapping vehicle
HINT: Have a battery ready as the power source to deploy the
airbag.
1. DISCONNECT NEGATIVE (±) TERMINAL CABLE FROM THE BATTERY
CAUTION: Work must be started after 90 seconds from
the time the ignition switch is turned to the LOCK posi-
tion and the negative (±) terminal cable is disconnected
from the battery (See page RS±2).
2. DISCONNECT AIRBAG CONNECTOR
(a) Remove the glove compartment door finish plate inside the glove compartment.
NOTICE: When handling the airbag connector, take care
not to the airbag wire harness.
(b) Pull up the connector.
(c) Disconnect the airbag connector.
3. CONFIRM FUNCTIONING OF SST (See page RS±27)
SST 09082±00700
4. INSTALL SST
(a) Connect the SST connector to the front passenger airbag assembly connector.
NOTICE: To avoid damaging the SST connector and wire
harness, do not lock the secondary lock of the twin lock.
SST 09082±00700
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SUPPLEMENTAL RESTRAINT SYSTEM FRONT PASSENGER AIRBAG ASSEMBLYRS±35
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When disposing of front passenger
airbag assembly only
When disposing of the front passenger airbag assembly
only, never use the customer's vehicle to deploy the air-
bag.
Remove the front passenger airbag assembly from the ve-
hicle and be sure to follow the procedure given below when
deploying the airbag.
HINT: Have a battery ready as the power source to deploy the
airbag.
1. REMOVE FRONT PASSENGER AIRBAG ASSEMBLY CAUTION:
w When removing the front passenger airbag assembly,
work must be started after 90 seconds from the time the
ignition switch is turned to the LOCK position and the
negative (±) terminal cable is disconnected from the
battery.
w Store the front passenger airbag assembly with the
airbag door facing up.
2. FIX FRONT PASSENGER AIRBAG ASSEMBLY TO TIRE
Using a service±purpose wire harness for vehicle, tie down
the front passenger airbag assembly to the tire.
Wire harness: Stripped wire harness section
1.25 mm
2 or more (0.0019 in2 or more).
HINT: To calculate the square of the stripped wire harness
section±
Square = 3.14 x (Diameter)2 divided by 4
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SUPPLEMENTAL RESTRAINT SYSTEM FRONT PASSENGER AIRBAG ASSEMBLYRS±37
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COMPONENTS
RS045±01
FRONT AIRBAG SENSOR
REMOVAL AND INSTALLATION
RS046±01
NOTICE:
wIf the wiring connector of the supplemental restraint
system is disconnected with the ignition switch at ON or
ACC, diagnostic trouble codes will be recorded.
w Never use SRS parts from another vehicle. When
replacing parts, replace with new parts.
w Never reuse the sensor involved in a collision when the
SRS has deployed.
w Never repair a sensor in order to reuse it.
RS±42±
SUPPLEMENTAL RESTRAINT SYSTEM FRONT AIRBAG SENSOR
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1. DISCONNECT NEGATIVE (±) TERMINAL CABLE FROMBATTERY
CAUTION: Work must be started after 90 seconds from
the time the ignition switch is turned to the ªLOCKº posi-
tion and the negative (±) terminal cable is disconnected
from the battery.
(See page RS±2)
2. REMOVE ENGINE UNDER COVER
(See page BO±12)
3. REMOVE FRONT AIRBAG SENSOR
(a) Disconnect the connector.
(b) Remove the bolt, the nut and the sensor.
4. INSTALL FRONT AIRBAG SENSOR
(a) Install the sensor with the arrow on the sensor facing toward the front of the vehicle.
Torque: 25 N Vm (260 kgf Vcm, 19 ft Vlbf)
NOTICE:
w Make sure the sensor is installed to the specified torque.
w If the sensor has been dropped, or there are cracks, dents
or other defects in the case, brackets or c onnector,
replace the sensor is removed, always replace the set bolt
and the nut with new one.
w The sensor set bolt and the nut have been anti±rust
treated. When the sensor is removed, always replace the
set bolt and the nut with new ones.
w After installation, shake the sensor to check that there is
no looseness.
w The front sensor is equipped with an electrical
connection check mechanism. Be sure to lock this
mechanism securely when connecting the connector. If
the connector is not securely locked, a malfunction code
will be detected by the diagnosis system.
w Check that the dimensions of the body where the front
airbag sensor is installed match those in the body
dimension drawings in the BODY section.
(The SRS may malfunction, or may not work, if the
dimensions of the sensor mount is not correct.)
5. INSTALL ENGINE UNDER COVER
6. CONNECT NEGATIVE (±) TERMINAL CABLE TO BATTERY
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SUPPLEMENTAL RESTRAINT SYSTEM FRONT AIRBAG SENSORRS±43
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