1991 LEXUS SC400 light

Parts Replacement ± Stoplights
(Rear Combination Light)
(See page BE±56 )
(High Mount Stop Light)
REPLACEMENT OF HIGH MOUNT STOP
LIGHT
1. REMOVE HIGH MOUNT STOP LIGHT
(a) Disconnect negative (±) terminal from the battery.
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.
(w/o Rear Spoiler)
(b) Separate the woofer speaker cover from package tray
trim.
(c) Disconnect connector.
(d) Remove woofer speaker cover.
(e) Remove five screws and separate the high mount stop light from woofer speaker cover.
(w/ Rear Spoiler)
(f) Separate the rear spoiler from the luggage door. (See page BO±106 )
(g) Remove three screws and separate the high mount stop
light from rear spoiler.
2. INSTALL HIGH MOUNT STOP LIGHT For installation, follow the removal procedure in reverse.
Parts Inspection± Stop Light System
(Stop Light Switch)
STOP LIGHT SWITCH
REMOVAL AND INSTALLATION OF STOP
LIGHT SWITCH
1. REMOVE STOP LIGHT SWITCH
(a) Remove instrument panel subassembly cover underNo.1 and brake pedal return spring.
(b) Disconnect connector.
(c) Remove a nut and switch.
2. ADJUSTMENT OF STOP LIGHT SWITCH (See page BR±4)
3. INSTALL STOP LIGHT SWITCH For installation, follow the removal procedure in reverse.
±
BODY ELECTRICAL SYSTEM Lighting SystemBE±61
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INSPECTION OF STOP LIGHT SWITCH
INSPECT STOP LIGHT SWITCH(Continuity)
Inspect the switch continuity between terminals.
If continuity is not as specified, replace the switch.
(Switch Circuit)
Disconnect the connector from the switch and inspect the
connector on the wire harness side as shown.
Check forTester connectionConditionSpecified value
Voltage2±GroundConstantBattery voltage
If circuit is not as specified, inspect power source or wire har-
ness.
(Light Failure Sensor)
REMOVAL AND INSTALLATION OF
LIGHT FAILURE SENSOR
1. REMOVE LIGHT FAILURE SENSOR(a) Remove luggage front trim cover.
(b) Remove a clip and disconnect connector.
(c) Remove light failure sensor.
2. INSTALL LIGHT FAILURE SENSOR For installation, follow the removal procedure in reverse.
BE±62
±
BODY ELECTRICAL SYSTEM Lighting System
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INSPECTION OF LIGHT FAILURE
SENSOR
INSPECT LIGHT FAILURE SENSOR(Relay Circuit)
Disconnect the connector from the sensor and inspect the
connector on the wire harness side as shown.
Check forTester connectionConditionSpecified value
Continuity1±GroundConstant*Continuity
2±GroundConstant*Continuity
3±GroundConstant*Continuity
9±GroundConstant*Continuity
11±GroundConstantContinuity
Voltage3±GroundTail or HeadOFFNo voltage
ONBattery voltage
4±GroundIgnition switchLOCK or ACCNo voltage
ONBattery voltage
7±GroundStop light switchOFFNo voltage
ONBattery voltage
Voltage8±GroundIgnition switchLOCK or ACCNo voltage
ONBattery voltage
*: There is resistance because this circuit is grounded through the bulb*: There is resistance because this circuit is grounded through the bulb.
If circuit is as specified, replace the sensor. If the circuit is not
as specified, refer to BE±60 wiring diagram and inspect the
circuits connected to other parts.
±
BODY ELECTRICAL SYSTEM Lighting SystemBE±63
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Troubleshooting
Stop Light System
You will find the cause of trouble more easily using the table shown. In t\
his table, the numbers indicate the order
priority of the causes in trouble. Check each part in the order shown. If nece\
ssary, replace the parts.
See pagePart
name
Trouble
Stop light does not light up.
Stop light always lights up.
Only one light always lights up.
Only one light does not light up.
BE±4
, 20
BE±61
BE±62
BE±6
STOP Fuse
Stop Light Switch
Light Failure Sensor
Wire Harness
Bulb
BE±64±
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(TURN SIGNAL AND HAZARD WARNING
LIGHT SYSTEM)
Description ± TURN SIGNAL AND
HAZARD WARNING LIGHT SYSTEM
The component parts of this system and their function are as shown in the f\
ollowing table.
Parts NameFunction
Turn Signal SwitchSwitches current from the turn signal flasher to the left side or right \
side.
Hazard Warning
SwitchModifies the circuit to the flasher relay and turn signal switch in acco\
rdance with the
respective switch positions.
Turn Signal FlasherReceives current from the hazard warning switch and flashes the turn sig\
nal lights by
switching the current to the lights ON and OFF.
PARTS LOCATION ± TURN SIGNAL
±
BODY ELECTRICAL SYSTEM Lighting SystemBE±65
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WIRING AND CONNECTOR DIAGRAMS
Turn Signal and Hazard Warning Lights
BE±66±
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Parts Replacement (Turn Signals)
(Cornering Light)
REPLACEMENT OF CORNARING LIGHT
1. REMOVE CORNARING LIGHT(a) Disconnect negative (±) terminal from the battery.
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 front under cover. (See page BO±92 )
(c) Remove a screw and two nuts.
(d) Remove cornaring light from bumper.
(e) Disconnect connector.
2. INSTALL CORNARING LIGHT For installation follow the removal procedure in reverse.
(Front Turn Signal Light)
REPLACEMENT OF FRONT TURN
SIGNAL LIGHT
(See page BE±37 )
HINT: Replacement of Headlight (LO±Beam)
(Rear Combination Light)
(See page BE±56 )
±
BODY ELECTRICAL SYSTEM Lighting SystemBE±67
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Parts Inspection (Turn and Hazard)
(Combination Switch Assembly)
(See page BE±39)
HINT: Inspect turn signal light switch.
(Turn Signal Flasher)
REMOVAL AND INSTALLATION OF TURN
SIGNAL FLASHER
(See page BE±16 )
INSPECTION OF TURN SIGNAL
FLASHER
INSPECT TURN SIGNAL FLASHER
(Operation)
LHD Side
(a) Connect the positive (+) lead from the battery to terminal
1 and the negative (±) lead to 4.
(b) Connect the two turn signal light bulbs parallel to each other to terminals 3 and 4, check that bulbs flash.
RHD Side
(c) Connect the positive (+) lead from the battery to terminal
1 and the negative (±) lead to 2.
(d) Connect two turn signal light bulbs parallel to each other
to terminals 2 and 5, check that the bulbs flash.
HINT: The turn signal lights should flash 60 to 120 times per
minute.
If one of the front or rear turn signal lights has an open circuit,
the number of flashes will be more than 140 per minute.
If operation is not as specified, replace the flasher.
(Flasher Circuit)
(See page BE±23 )
(HAZARD WARNING SWITCH)
REMOVAL AND INSTALLATION OF
HAZARD WARNING SWITCH
1. REMOVE INSTRUMENT PANEL NO.2 REGISTER
ASSEMBLY
(See page BO±111 )
2. REMOVE HAZARD WARNING SWITCH Remove two screws and hazard warning switch from register.
3. INSTALL HAZARD WARNING SWITCH AND REGISTER
For installation, follow the removal procedure in reverse.
BE±68
±
BODY ELECTRICAL SYSTEM Lighting System
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