1991 LEXUS SC400 fuse

Wiring Diagram
CENTER AIRBAG SENSOR ASSEMBLY CONNECTOR
No.SymbolTerminal NameNo.SymbolTerminal Name
18E2Ground
2±SRRH Front Airbag Sensor (±)9LAAirbag Warning Light
3+SRRH Front Airbag Sensor (+)10D±Squib (±)
4+SLLH Front Airbag Sensor (+)11D+Squib (+)
5±SLLH Front Airbag Sensor (±)12TcDiagnosis
6+BBattery (ECU±B Fuse)13E1Ground
7IG2Power Source (IGN Fuse)14AccPower Source (CIG Fuse)
AL1Electrical Connection Check
MechanismBL2Electrical Connection Check
Mechanism
AB±33SRS AIRBAG ± Troubleshooting
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4. Read the diagnostic trouble code indicated by thenumber of times the O/D OFF indicator light blinks.
HINT: If the system is operating normally, the light will blink
2 times per second.
The malfunction code is indicated as shown in the illustration
at left (Diagnostic trouble code ª42º is shown as an example).
HINT: When 2 or more trouble codes are stored in memory,
the lower±numbered code is displayed first.
If no diagnostic trouble code is output, or if a diagnostic
trouble code is output even though no diagnostic trouble
code output operation is performed, check the TE1 terminal
circuit on page AT±118.
DIAGNOSTIC TROUBLE CODE CHECK
BY USING LEXUS HAND±HELD TESTER
AT0RD±01
1. Hook up the LEXUS hand±held tester to the DLC2.
2. Read the diagnostic trouble codes by following theprompts on the tester screen.
Please refer to the LEXUS hand±held tester operator's
manual for further details.
CANCELING DIAGNOSTIC TROUBLE
CODE
AT09T±07
After repair of the trouble area, the diagnostic trouble code
retained in the ECM memory must be canceled out by remov-
ing the EFI fuse for 10 seconds or more, with the ignition
switch off.
Check that the normal code is output after connecting the
fuse.
AT±38
±
A304E (1UZ±FE) AUTOMATIC TRANSMISSION TROUBLESHOOTING
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Troubleshooting
You will find the cause of trouble more easily by properly using the table \
shown below. In this table, the
numbers indicate the order of priority of the causes of trouble. Check each part in \
the order shown. If neces-
sary, replace the part.
See page
BE±4 ,21BE±4,21BE±4,20BE±4,20BE±156BE±152BE±149BE±151BE±152BE±26BE±392BE±4,20 ±±
Part
name
Trouble
AM1 FuseDOME FuseDOOR FusePOWER FuseTheft Deterrent and Door Lock Control ECUPower Window Main RelayPower Window Master SwitchPower Window SwitchPower Window MotorIgnition SwitchDoor Open Detection SwitchECU±IG FuseWire Harness
*1 Power window does not operate.1234
*2 Power window does not operate.35467218
ªOne Touch Power Window Systemº does
not operate.1
Only one window glass does not move.1234
ªWindow Lock Systemº does not operate1
ªWindow Lock Illuminationº does not light
up.1
Key±off power window does not operate124536
*1: Dook Lock does not operate.
*2: Dook Lock is normal.
±
BODY ELECTRICAL SYSTEM Power Window Control SystemBE±157
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LIQUID CRYSTAL INNER MIRROR
SYSTEM
Description
The liquid crystal inner mirror replaces the previous mirror, which mechanically switched between the ªDayº and
ªNightº settings, with liquid crystal inside the mirror which changes the bright\
ness of the mirror surface. The com-
ponent parts of this system and their functions are shown in the table below.
Parts NameFunction
Liquid Crystal Inner
MirrorReceives current from the fuse DOME and changes the surface brightness o\
f the mirror
when switch is operated.
Key Unlock Warning
SwitchOpens the circuit so that the mirror can be operated only when the ignit\
ion key is set.
Parts Location
BE±164±
BODY ELECTRICAL SYSTEM Liquid Crystal Inner Mirror System
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(b) Press the mirror switch and check if the mirrors surfacerepeatedly becomes ºbrightº and ºdarkº.
If operation is not as specified, replace the liquid crystal inner
mirror.
(Circuit)
Disconnect the inner mirror connector and inspect the con-
nector on the wire harness side as shown.
Check forTester connectionConditionSpecified value
Voltage2±GroundConstantBattery voltage
Continuity1 GroundIgnition key setContinuityContinuity1±GroundIgnition key removedNo continuity
If circuit is not as specified, refer to BE±165 wiring diagram
and inspect the circuits connected to other parts.
(Key Unlock Warning Switch)
(See page BE±26)
Troubleshooting
You will find the cause of trouble more easily by properly using the table \
shown below. In this table, the numbers
indicate the order of priority of the cruses of trouble. Check each part in the \
order shown. If necessary, replace
the part.
See pageBE±4,21BE±165BE±26 ±±
TroubleParts
name
DOME FuseLiquid Crystal Inner MirrorKey Unlock Warning SwitchWire Harness
Liquid Crystal Inner Mirror does not operate.1234
BE±166±
BODY ELECTRICAL SYSTEM Liquid Crystal Inner Mirror System
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Troubleshooting
You will find the cause of trouble more easily properly using the table sho\
wn below. In this table, the numbers
indicate the order priority of the causes of trouble. Check each part in the order shown. If necessary, replace
the part.
See pageBE±4,20BE±168BE±169 ±±
TroubleParts
name
GAUGE FuseTension Reducer SolenoidBuckle SwitchWire Harness
Tension Reducer does not operate.
(Driver's and Passenger's)12
Tension Reducer does not operate. (Only one side)213
BE±170±
BODY ELECTRICAL SYSTEM Electric Tension Reducer System
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DEFOGGER SYSTEM
Description
The component parts of this system and their functions are described in the\
following table.
Parts NameFunction
DefoggerWhen over current flows in the defogger circuit, the Defogger fuse break\
s the circuit
to protect it against damage.
Defogger RelayThis relay is supplied with current from terminal IG1 of ignition switch\
(Ignition switch ON)
and switches large current from the defogger.
A/C Control Panel
Assembly

Defogger SwitchThe defogger switch is built into the A/C Control Panel Assembly. This switch is
supplied with current from the relay and fuse HTR. Grounds current from \
the defogger
relay, turning the defogger relay ON.
Defogger

Rear Window

Outer MirrorThese defoggers generate heat when current is supplied from the defogger\
relay.
Parts Location
±
BODY ELECTRICAL SYSTEM Defogger SystemBE±171
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INSPECTION OF MIRROR DEFOGGER
INSPECT MIRROR DEFOGGER(a) Connect the positive (+) lead from the battery to terminal
7 and the negative (±) lead to terminal 8.
(b) Check that the mirror becomes warm.
HINT: It will take a short time for the mirror to become warm.
If the mirror does not become warm, replace the mirror as-
sembly.
Troubleshooting
You will find the cause of trouble more easily using the table shown below. In this table, the number indicate
the order priority of the causes in trouble. Check each part in the order s\
hown. If necessary, replace the parts.
See pageBE±4 ,20BE±4,20BE±4,22BE±172BE±173 ±±BE±173 ±±BE±174
TroubleParts
name
HEATER FuseMIR±HTR FuseDEFOG FuseDefogger SwitchDefogger RelayWire HarnessDefogger WiresCKE CoilMirror Defogger
All defogger systems do not operate.11234
Rear window defogger does not operate.312
Mirror Defogger does not operate.132
±
BODY ELECTRICAL SYSTEM Defogger SystemBE±175
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