lock LEXUS SC400 1991 Service Repair Manual

(Switch circuit)
Connect the switch connector and inspect the connector on
the wire harness side from the back side as shown.
Check forTester connectionConditionSpecified value
Voltage2±GroundIgnition switch turned to ONBattery voltage
3±GroundIgnition switch turned to ACC or ON
4±GroundConstant
5±GroundIgnition switch turned to START
6±GroundIgnition switch turned to ON
11±GroundConstant
If circuit is not as specified, inspect the switch or refer to
BE±25 wiring diagram and inspect the circuits connected to
other parts.
2. INSPECT KEY UNLOCK WARNING SWITCH
(Switch continuity)
Inspect the switch continuity between terminals.
Terminal
Switch position
ON
OFF
(Ignition Key removed)
(Ignition Key set)
If continuity is not as specified, replace the switch.
(Switch circuit)
Connect the switch connector and inspect the connector on
the wire harness side from the back side as shown.
Check forCheck connectionConditionSpecified value
Continuity10±GroundIgnition key removedNo continuity
Ignition key setContinuity
9±GroundConstantContinuity
If circuit is not as specified, inspect the switch or wire harness.
±
BODY ELECTRICAL SYSTEM Ignition SwitchBE±27
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Parts Replacement ± Headlight
(Headlight)
REPLACEMENT OF HEADLIGHT
1. REMOVE HEADLIGHT(a) Remove battery (LH) or disconnect negative termial (±)from the battery (RH).
CAUTION: Work must be started after approx. 20 se-
conds or longer from the time the ignition switch is
turned to the ºLOCKº position and negative (±) terminal
cable is disconnected from the battery.
(b) Remove fender liner. ( BO±92)
(c) Remove a screw and two nuts.
(d) Disconnect connector.
(e) Remove headlight (Low Beam).
(f) Disconnect connector.
(g) Remove front bumper. ( BO±12)
(h) Remove the bolt.
(i) Remove headlight (High±Beam).
2. INSTALL HEADLIGHT For installation, follow the removed procedure in reverse.
±
BODY ELECTRICAL SYSTEM Lighting SystemBE±37
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5. REMOVE COMBINATION SWITCH ASSEMBLY(a) Remove four screws.
(b) Disconnect connectors.
(See page BE±41)
HINT: Since the airbag connector has a 2±stage lock, remove
the 1st stage lock, and disconnect the connector.
(c) Remove combination switch assembly from steering column.
HINT: Pull the wire harness spool body to forward and re-
move wire harness spool body from steering column.
INSPECTION OF COMBINATION SWITCH
For installation, follow the removal procedure in reverse.
(MAIN POINT OF INSTALLATION)
1. ADJUSTMENT OF SPIRAL CABLE (a) Check that the front wheels are facing straight ahead.
(b) Turn the spiral cable counterclockwise by hand until itbecomes harder to turn the cable.
(c) Then rotate the spiral cable clockwise about 3 turns to align the red mark.
HINT:
w The spiral cable will rotate about 3 turns to either left or
right of the center.
w The connector should be straight up.
(d) Install the steering wheel so that the match marks will not be misaligned.
2. INSTALL STEERING SET NUT
Torque: 35 N Vm (360 kgf Vcm, 26 ft Vlbf)
3. INSTALL STEERING WHEEL CENTER PAD
Torque the torx screws.
Torque: 7.1 N Vm (75 kgf Vcm, 62 in.lbf) V
BE±40±
BODY ELECTRICAL SYSTEM Lighting System
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1. REMOVE WIRE HARNESS SPOOL COVERPry loose three locking lugs.
2. REMOVE CONNECTOR FROM SPOOL BODY (a) Pry loose two locking lugs and separate the connectorfrom spool body.
(b) Remove the separator from spool body.
3. REMOVE WIRE HARNESS HOLDER (a) Pry loose three locking lugs.
(b) Pull out the wire harness.
(c) Remove two screws and the wire harness holder.
4. REMOVE SPIRAL CABLE SUBASSEMBLY (a) Disconnect the connector (White).
(b) Remove the four screws and spiral cable subassembly.
BE±42
±
BODY ELECTRICAL SYSTEM Lighting System
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5. REMOVE WIRE HARNESS CLAMPRemove three screws and wire harness clamp.
6. SEPARATE CONNECTOR (a) Pry loose two locking lugs.
(b) Separate two connectors from connector assembly.
7. REMOVE TERMINALS FROM CONNECTOR (32p connector)
(a) Pull out two inner terminal covers.
CAUTION: Do not remove terminal for AIRBAG connec-
tor (Yellow).
(b) From the open end, insert a miniature screwdriver
between the locking lug and terminal.
(c) Pry down the locking lug with the screwdriver and pull the terminal out from the rear.
8. REMOVE LIGHT CONTROL SWITCH (a) Remove the two screws, and separate the bracket from
switch body.
±
BODY ELECTRICAL SYSTEM Lighting SystemBE±43
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ASSEMBLY OF COMBINATION SWITCH
INSTALL PARTS OF COMBINATION SWITCH IN RE-
VERSE SEQUENCE OF DISASSEMBLY
(MAIN POINT OF INSTALLATION)
1. INSTALL LIGHT CONTROL SWITCH(a) Slide the switch and install the switch body.
(b) Set the lever in the HI position, and install the ball andplate.
(c) After installing the light control switch to the switch body,
insure that the switch operation is smooth.
2. INSTALL TERMINALS TO CONNECTOR wPush in the terminal until it is securely locked in the
connector lug.
w Install each switch terminal as shown in the figure.
±
BODY ELECTRICAL SYSTEM Lighting SystemBE±45
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(Integration Relay)
REMOVAL AND INSTALLATION OF
INTEGRATION RELAY
(See page BE±16)
INSPECTION OF INTEGRATION RELAY
INSPECT INTEGRATION RELAY
(Relay Circuit/Light Auto Turn Off System)
Remove the relay from junction block and inspect the con-
nectors on the wire harness and junction block side as shown
in the chart.
(USA)
Check forTester connectionConditionSpecified value
ContinuityA4±GroundPassenger 's CourtesyOFFNo continuityygy
ONContinuity
A5±GroundIgnition KeyPull offNo continuitygy
Put inContinuity
A6±GroundDriver's CourtesyOFFNo continuityy
ONContinuity
A8±GroundSeat BeltUnfastenContinuity
FastenNo continuity
A10±GroundConstantContinuity
B1±GroundPassenger's DoorUnlockContinuityg
LockNo continuity
B2±GroundDriver's DoorUnlockContinuity
LockNo continuity
B3±GroundLight Control SwitchOFFNo continuityg
TAIL or HEADContinuity
B6±GroundLight Control SwitchTAIL or OFFNo continuityg
HEADContinuity
VoltageA1±GroundConstantVoltageg
A2±GroundConstant*Voltage
A7±GroundIgnition SwitchONVoltageg
LOCK or ACCNo voltage
A9±GroundIgnition SwitchONBattery voltageg
LOCK or ACCNo voltage
A11±GroundIgnition SwitchON or ACCVoltageg
LOCKNo voltage
* There is resistance because this circuit is grounded through the bulb.\
±
BODY ELECTRICAL SYSTEM Light SystemBE±49
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(Canada)
Check forTester connectionConditionSpecified value
ContinuityA4±GroundPassenger's CourtesyOFFNo continuityygy
ONContinuity
A5±GroundIgnition KeyPull offNo continuitygy
Put inContinuity
A6±GroundDriver's CourtesyOFFNo continuityy
ONContinuity
A8±GroundSeat BeltUnfastenContinuity
FastenNo continuity
A10±GroundConstantContinuity
A12±GroundConstantContinuity
B1±GroundPassenger's DoorUnlockContinuityg
LockNo continuity
B2±GroundParking Brake
Switch PositionOFF (Switch pin
pushed in)No continuity
ON (Switch pin re-
leased)Continuity
B3±GroundDriver's DoorUnlockContinuity
LockNo continuity
B7±GroundHeadlight Dimmer
Switch PositionLow Beam or High
BeamNo continuity
FlashContinuity
B8±GroundHeadlight DimmerLow BeamNo continuityg
Switch PositionHigh Beam or FlashContinuity
B10±GroundLight Control SwitchOFFNo continuityg
HEAD or TAILContinuity
B12±GroundConstantContinuity
B13±GroundLight Control SwitchOFF or TAILNo continuityg
HEADContinuity
VoltageA1±GroundConstantVoltageg
A2±GroundConstant*Voltage
A7±GroundIgnition SwitchONVoltageg
LOCK or ACCNo voltage
A9±GroundIgnition SwitchON*Voltageg
LOCK or ACCNo voltage
A11±GroundIgnition SwitchON or ACCVoltageg
LOCKNo voltage
B4±GroundEngineSTOPNo voltageg
RunningVoltage
B11±GroundConstantVoltage
* There is resistance because this circuit is grounded through the bulb.\
If the circuit is as specified, trying replacing the relay with a
new one.
If the circuit is not as specified, refer to BE±35 wiring diagram
and inspect the circuit connected to other parts.
BE±50
±
BODY ELECTRICAL SYSTEM Light System
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Parts Replacement ± Taillights
(Clearance Light)
REPLACEMENT OF CLEARANCE LIGHT
(See page BE±37)
HINT: Replacement of Headlight (LO±Beam).
(FRONT SIDE MARKER LIGHT)
REPLACEMENT OF FRONT SIDE
MARKER LIGHT
1. REMOVE FRONT SIDE MARKER LIGHT (a) Disconnect negative (±) terminal from the battery.
CAUTION: Work must be started after approx.20
seconds from the time the ignition switch is turned to the
ºLOCKº position and negative (±) terminal cable is
disconnected from the battery.
(b) Remove fender liner. BO±92)
(c) Remove two nuts.
(d) Remove front side marker light from bumper.
(e) Disconnect connector.
2. INSTALL FRONT SIDE MARKER LIGHT For installation, follow the removal procedure in reverse.
(Light Failure Sensor)
See page BE±62
(Integration Relay)
See page BE±49
(Rear Combination Assembly)
REPLACEMENT OF REAR
COMBINATION LIGHT ASSEMBLY
1. REMOVE REAR COMBINATION LIGHT ASSEMBLY
(a)Disconnect negative (±) terminal from the battery.
CAUTION: Work must be started after approx. 20
seconds from the time the ignition switch is turned to the
ºLOCKº position and negative (±) terminal cable is
disconnected from the battery.
±
BODY ELECTRICAL SYSTEM Lighting SystemBE±55
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(b) Remove the luggage compartment trim.
(c)Disconnect connector.
(d) Remove four nuts and rear combination light assembly.
2. INSTALL REAR COMBINATION LIGHT ASSEMBLY Follow the removal procedure in reverse to carry out installa-
tion.
(License Plate Light)
REPLACEMENT OF LICENSE PLATE
LIGHT
1. REMOVE LICENSE PLATE LIGHT(a) Disconnect negative (±) terminal from the battery.
CAUTION: Work must be started after. 20 seconds from
the time the ignition switch is turned to the ºLOCKº posi-
tion and negative (±) terminal cable is disconnected from
the battery.
(b) Remove the rear bumper.
(c) Disconnect connector.
(d) Remove three screws and the license plate light.
2. INSTALL LICENSE PLATE LIGHT
Follow the removal procedure in reverse to carry out
installation.
BE±56
±
BODY ELECTRICAL SYSTEM Lighting System
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