fuse LEXUS SC300 1991 Service Repair Manual

OVERALL ELECTRICAL WIRING DIAGRAM
1234
18 LEXUS SC300
1J
7 2
3 1J
5
1B
4 2
4 1C
6
4
ACC
IG1
ST1
AM1 2
4
7 9A 10A
8BS1
10 19 22 25 23 18 12 11 24 6 1 394 105
416 5
612
4B 5A 12A 5B 12B 8A 8B 1B 6B 2B 7B 2A 7A
6 20 Bc1 4 Bc2 3 Bc2 19 Bc1 16 Bc1 5 Bc1 17 Bc1 6 Bc1 15 Bc1 7 Bc2 4 Bc1 8 Bc2
10 IP1 1 I P15BT1 6BT1 11 A
6A
1A
11 B
19 BT1
20 BT1
18 Bc1 4 BS1 81514317
EB
16543 8 7 2
52
3A
W± L W± L W
B±Y
B±R W
W
W± L
R
Y± B
B
Y
O R
BR
GR±W
G
R± W G
W
B
B
W±B
W± B W
BR
W
L±R W
W
L±R R±L
R±L L±O
L±Y
L±B
B±Y B±R L
LG
L
LG V
V
LG L
LG
L
B±R B± YL±B
L±Y
L±O L
R±B BR
G± W
R±W
L±W
B±W
LG
L
15A
ECU± I G
15A
TEL
40A
IGSW
G±B
R
60A MAIN 100A AM1
120A ALT
BATTERY
F9
FUSE BLOCK
From Radio and Player
(
w/ CD Player )
< 19±1>
Fr om Stereo Power
Amplifier
( w/o CD Player )
< 20±1>
To Radio and Player
< 19±1> < 20±3>
F12
FRONT DOOR
SPEAKER RH MIC+ GND
M1
MOBILE PHONE
TEL EP HONE TRA NS CE I VE R
C1 6
TELEPHONE
MICROPHONE
[COMB. SW]
TELEPHONE TRANSCEI VER AND SPEAKER RELAY
SPEAKER RELAY B
Power
Source Cellular Mobile Telephone
(
SHI ELDED )
(
SHIELDED )
(SHI ELDED )
(
SHIELDED )
(SHI ELDED )
(
SHIELDED )W
I15
IGNITION SW
T16 A , T17 B 2
3
5
7
8
9
10
12 4
11 1
6 5
4
3
2
1
6789101112
AB
TELEPHONE TRANSCEIVER AND SPEAKER RELAY
T16 T17
12 Fr ont s ide of
left fender
10
9
BR BR BR
BR±W BR±W BR±W
BR BR
BR±W
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1234
19 LEXUS SC300
4ACC
IG1
ST1
AM1 3
2
3BV1
2 BV2 1 BV2 6 IQ2 7 I Q2 4 BV2 3 BV2 10 BV2 9 BV2 6 BV1 5 BV1 4 BV1
10 I F2 1 IF22IG2 1IG2 11Bc2 12Bc2
10 BV1
11 IQ2 3 IQ1
7 BV2 2 BV1 19 BV1 7 BV1 18 BV1
3IG2
1Bc2
10 Bc 1
9Bc1
8Bc1
23 Bc1
8 BV2
12 IQ2 24 Bc 1
II BM 1J
5
1J
8
2
1C
6
1E
10
2
1B
4 1J
7
AMP E
MU TE A MP RU ± RU +
7A
10 C
4C
8A
3A
4A
3D
1D
6D
2D
3C
1A
6 5A 2A 6A 1B 3B 2B 6B 1C 5C 9C 2C
74
MU TE
AMP
RU±
RU+
RL±
RL +
RR±
RR+
FL±
FL+
FR±
FR+ TLMT PWR VOL+ VOLC SGND B ACC ANT ANTA ANTB WP+ WP± ACC +B E ANTB ANTA ANT ACC B IG
6
3
8
5
2
1
7
3
4
9
10
26 5 1 47
B
W
P±L
R± B BR
R± B P±L
W B Y B
W R
V
V
V
R
W B
Y
B
W
P±L
BR
BR P± L
W± B Y± R
L±W
P±G GR
L±Y
B±R
R±W
B±W
GR
L±Y
BR
L±Y
GR L±Y
GR
P± G
L±W Y±R L±Y
G±RL±YGR
P± G
L±W Y±R
Y±R
L±WP±G GR
L±Y L±Y W
P±L
VV
G±RR±L
R± W G± Y W
W± L W
LG L
P
P
P
P
V LG
L W
BR
BR
B±Y
P±L
B±Y
E
1 11 2
2 22 1
60A MAIN
100A AM1
120A ALT
40A
IGSW I15
IGNITION SW
BATTERY 20A
RADIO No. 1
7. 5A
RA DI O No. 2
RADIO AND PLAYER
F9
FUSE BLOCK A3 2
AUTO ANTENNA MOT OR AND REL AY
W1 0
WOOF ER SPEAKER
AMPLIFIER
W9
WOOFER
SPEAKER
R12
REAR
SPEAKER LH
R13
REAR
SPEAKER RH
F1 0
FRONT DOOR
SPEAKER LH
15A
ECU±I G
To Telephone Tr ans ceiv er
and Speaker Relay
< 18±7>
To A/ C Cont rol Sw
and Radio Sw
< 22±4>
To A/ C Cont rol Sw
and Radio Sw
< 22±4>
To Telephone Transc eiver
and Speak er Relay
< 18±7>
Power
Source
Radio and Player
(
w/ o CD Player )
Auto Antenna
2IE1L±Y
( SHI ELDED )
P± L (
SHI EL DED )
R2 ,R3 ,R5 , R6
CDA B 12
5
34
678910 12
3456
12 34
5678910 12
3456
CD A B
R2 R3 R5 R6 RADIO AND PLAYER
L±Y
GR
3
4
Under the
as htr ay RHBack panel
center
8
7
BR
Y B
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OVERALL ELECTRICAL WIRING DIAGRAM
1234
20 LEXUS SC300 (
Cont . ne xt pa ge )
4 ACC
IG1
ST1
AM1 3
2
1J
7
1B
4
5
BV3 4
BV3 15
BV3 14
BV3 13
BV3 12
BV3 1
BV3 8
BV3 11
BV3 10
BV3 3
BV3 2
BV3 16
BV3 10
BV1 11
IQ2 2
IE1
3
IG2 2
2
74 3F 8F 9F 10F 1F 6F 11F 2F 7F 4F 5F 12F 3E 2C 6C 1C 3C 4D
6 1G 3G 2G 6G 1H 5H 8H 2H 6H 9H 4H 3H
3
IQ1 7
BV2
2
BV1 1
BV1 19
BV1 7
BV1 18
BV1
1J
8
1E
10
7D 6D 15D 14D 5D 13D 12D 11D 1E 5E 1D 2E 8D 4E 10E
3D
13
BV1
12
BV1
16
BV1
15
BV1
11
BV1
14
BV1
8
BV1
17
BV1
6
BV1
5
BV1
4
BV1
9
BV1
3
BV1
7H
B± Y
GR
L±Y
L±W B±RL±G
Y±R
R±B L±B
P± L W
BR B
G Y
W
BR L
R
L±YW
P±L
B± Y
W
W± L
W
G±WG± OY±R Y± L
B
W
BR
L
R
Y±B
V±W G±B
V
L±Y L±Y W
P±L
L±Y
L±Y
GR
L±Y
L±Y
P± G
L±W
Y±R GR
GR
L±Y
L±W B± R
L±G
Y± R
G±Y
R±W R± L
G± R V
G± B
V±W Y± B R
L
BR W
B
Y± L
Y±R
G± O
G±W
R L
BR
WY
G
BR±B BR
B
W
P±L
R± B
P±L
W
B
BR G
Y
W
BR
L
R
L±B R± B
GR
To Luggage Compar tment
light SW< 6±3>
From Telephon Tr ans ceiv er
and Speaker Relay< 18±1>
To A/C Control SW and Radio SW
< 22±4>
From A/C Control SW and Radio SW
< 22±4>
40A
IGSW I15
IGNITION SW
R± W
TXM+ TXM± TXS+ TXS± CDR+ CDR± SGND CDL+ CDL± GND +B ACC SW
TXM+ TXM± TXS+ TXS± CDR+ CDR± SGND CDL+ CDL± GND +B
BATTERY
60A MAIN 100A AM1
120A ALTF9
FUSE BLOCK F¥
RF¥ LR¥RR¥ L MUTE B E EP GND S GND RU+ RU± A MP MUTE
ACC TLMT PWR VOL+ VOLC SGN1 B ACC ANT ANTA ANTB
P±L
7 . 5A RA DI O No. 220A RADIO No. 1
CD PL AYER
CD A UTOMAT I C CHA NGE R
RA DI O A ND P LA YE R
Power
SourceRadio and Player
(
w/ CD Player )
(
SHI ELDED )
(
SHIELDED )
( SHIELDED )(
SHI ELDED)
( SHI EL DED )
( SHI EL DED )
(
PIONEER )
( PIONEER )
7 8
(
SHI EL DED )
C9 R2 , R3 , R4
F DCE
12
3456
12 34
5678910
GH
CD AUTOMATIC CHANGER
C2 0 C2 1
C20 , C21 GH
123 45
6789101112 F
CD PLAYER
C9 123 45
6 7 8 9 10 11 12
12
3456D
E
RADIO AND PLAYER
R2
R4 R3 C(
PI ONEER )
3
4
1234 567
8 9 10 11 12 13 14 15
BR BR
BR
BR
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OVERALL ELECTRICAL WIRING DIAGRAM
1234
21 LEXUS SC300 (
Cont . ne xt pa ge )
4 ACC
IG1
ST 1
IG2
AM1
3
2
6
11 AM2
1J
7
1B
4 16 IE1
20 IK110 IK2
1IE1
1J
31J 51J821B 2
1E
1E
18
1E 1H1E 2 1E
131B
IG1 20 3D
3A 4
3D
2
3C
6
3A
2
3F
1 2 1 6
3F 5
3C
5
3A
IK16
IK1 7
10 IJ1
IE110
IG118
EB
19 IG1
ED EA 13 IE2 14 IG3 W± R
R
Y
B± O Y± B
V±R V± Y
R± W
L±R
W
R±Y B
V±W V
R
L±R
P± L
R
L±R L±R
P± L
P± L
Y
B±O B±YP±L
W± L
R± W
B
W± B R±W
B
W
W
W±L
W± L W±L
W
W±R
Y±B
V±R
V± Y
R±WV±Y V± R Y±B
W± R
W
W± R
B± O
R±W R± W
B
B
R±W R±W
R±W V±Y
BR
W± B
R±W Y
W±B Y
R4713
21 11
4
12
8
7
9
2
1
2
340A IGSW
100A AM1
120A ALT
60A MAIN
30A INJ
30A AM2
14
9 I15
IGNITION SW
7. 5A I GN
10A GAUGE
15A CIG
10A DOME
15A ECU±B
From ABS ECU
<9±2>
From ABS ECU
< 8±5>
(
* 1 )
(
* 2)
6
BATTERY
F9
FUSE BLOCK
12
O2
OI L P RE SS URE SW
C5
COOLANT LEUEL
WARNING SW E6
ENGI NE OI L L EVEL
WARNING SW
P3
PARKI NG
BRAKE SWD2
DIODE
(f or Par king
Brake )
B1
BRAKE FLUID
LEVEL SW
B
B
R±W R±WR±W
R±W
B
B B
( Canada )
(
Canada )
( US A )
(USA )
(
US A )
(
US A )
(
Canada )
(
Canada )(
Canada )
(
* 2
) (
* 1)
(
US A )(
US A)
(
USA )
R±W
R± W
Fro m Dayt i me
Running Light
Relay< 4±4>
Fr om Cr uise Control
ECU< 16±2> T1 5
TRIP SW AND THEFT DETERRENT
I NDI CA TOR L I GHT
S3
SPEED SENSOR No. 1
From Tr act ion ECU
<8±7>
2
W
12 12 2 54 11 13 *
1: (
w/ Tr action Contr ol )
* 2: (
w/oTractionControl )
Power
Source Combination Meter
R±WL±R
R
4 3
SECURITY
M
H
SET
RESET A/ B
W1
WASHER
LEVEL SW
P± L
L±R
R W± R
From ABS ECU
<8±5>
( * 1)
R
R
10 11 12 13 17 18 19 20 21 12345 6789
14 15 16 12 34 56 78
9 10 1112 13 14 1516 1718
17 18
1 2345 6789 10
23
22
21
20
19
15
14
13
12
11 16
AB C
C12 C13 C14 COMBINATION METER
1 1
23
DE
FUEL SENDER
F1 7 F1 8
Rear side of
c ylinder head LH Fr ont side of
right fender Fr ont s ide of
left f ender
2
1
2 2
1 1
1
B
S HORT CONNE CTOR
1
2 12F
S23
G
S22
7BU1
From Tilt and
Power Telesc opic
ECU< 11±2>
GR
B
( M/T ) 3
G±B
From Theft Det err ent and
Door Lock ECU< 17±2>
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OVERALL ELECTRICAL WIRING DIAGRAM
1234
22 LEXUS SC300 (
Cont . ne xt pa ge )
4 ACC
IG1
ST 1
AM1 3
2
1J
7 21J
51K2
22 22
1B
4 2
1A
5
22 222 2 1
3
5 4
53
1
2
EB1 EB1 3IN1
2IN1
IN1
6
1IN1
12 IN1
EB I J 1 2
M
2 1 2
A 1
B
2
B
M
1A IJ1
2
5 4 216
4
6 12
4
74
3
W
B
P±L
B±Y
LW±G R W
P± L
R±L
L±W
G± Y
G±R R±L
R± W
BR±W G±W BR
R±Y V
W± G BR
G± Y
Y
B±R
BR±W G± W BR
R± Y V
W± B
L
BR
G±Y
RL±R
W± B
W± B W± B
W±B
W±B B
W± L W
W W
B
L
W
I15
IGNITION SW
40A IGSW
60A MAIN
120A ALT 100A AM1
F9
FUSE BLOCK
BATTERY
To Engine and
ECT ECU< 2±7>A/ C MAGNETI C
CL UTCH REL AY
10A HEATER 60A HEATER
To Radio and Player
< 19±3> < 20±2>
From Radio and Player
<19±3><20±1>
From Radio and Player
<19±3><20±1> To Radio and Player
< 19±3> < 20±2>
5 12
L±W
R±L
COOL
WARM
Power
Source Automatic Air Conditioner
R±L
R±LR±L
B
W±B W±B
B3
BLOWER
RESISTOR
(for Low
Speed )
A2
A/C LOCK SENSOR
AND A/C MAGNETIC
CLUTCH A17 , A18
A/C POWER TRANSISTOR
AB
A27
A I R MI X CONT ROL S ERV O MOTOR
HEATER
RELAY
B2
BLOWER
MOTOR Y
B±R A/ C POWER TRANSI ST OR
L±W
L±R
W
12
12
AB
A1 7 A1 8
A/C CONTROL ASSEMBLY
1 23 45 6
7 8 9 10 11 12 14 15
13 12 34
5 6 7 8 9 10 11 12 13 14 15 16 20 21 22 23 24 25 123456 7891011
17 18 19
EC D
A12 A13 A14
Front side of
lef t fender Ri gh t ki c k
panel
1
2
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OVERALL ELECTRICAL WIRING DIAGRAM
1234
23 LEXUS SC300(
Cont ' d )
5Ba2
BK
M
21
12
7W± B W± B L
L±B
P1 7
POWER SEAT MOTOR
( for Driver' s Seat
Si de Con t ro l )FRONT
REAR
SL I DE
Under the center
pillar LH
4Ba2
L±W
L±W
FRONT VERTICALUPP1 3
POWER SEAT MOTOR
(
for Driver' s Seat
Front Ver tical Cont rol )L±Y
DOWN
L±R
M
21
56 REAR VERTI CAL
UPP15
POWER SEAT MOTOR
(
for Rear Vert ical
Control )Y±G
DOWN
Y±L
M
21
98 LUMBAR SUPPORT
RE L EA SEP1 4
POWER SEAT MOTOR
(
for Driver' s Seat
Lumbar Support Control )G±R
PUSH
G
M
21
10 12
3
4 RE CL I NI NG
FRONTP16
POWER SEAT MOTOR
(
for Reclining
Motor Cont rol )Y±R
REAR
Y±B
M
21 11
P8
POWER SEAT CONTROL SW
(
for Driver' s Seat )
1C
8
1B
2
4
6
L±W
W± L
W
30A
DOOR
BATTERY100A AM1
120A ALT
F9
FUSE BLOCK
6
5
Power Seat
(
w/o Driving Positiotn Memory )
Power Source
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44
POWER SOURCE (Current Flow Chart)
The chart below shows the route by which current flows from the battery to \
each electrical source
(Fusible Link, Circuit Breaker, Fuse, etc.) and other parts.
The next page and following pages show the parts to which each electrica\
l source outputs current.
Taillight
Relay (Point Side)
30A AM260A MAIN 50A DEFOG
60A HEATER
7.5 TRAC
40A IG SW
120A ALT
Starter Relay
(Point Side)
Headlight Relay
(Point Side)
30A EFI
15A TEL
10A DOME
20A RADIO No. 1
25A HAZ±HORN
Theft Deterrent and
Door Lock ECU
15A HEAD RH
(USA) 15A HEAD LH
(USA)
Dimmer Relay
(Coil Side)
Starter
15A STOPIgnition SW
(AM1)
30A DOOR
15A TAIL
Alternator
ABS Motor Relay
(Point Side)
Defogger
Relay
Starter ABS
Actuator
10A MIR±HTR
15A ECU±B 7.5A PANEL
7.5 IGN
Engine ECU Traction Brake
Actuator
30A INJ
60A ABS No.1
Traction Brake
Main Relay
(Point Side)
ABS
Actuator Relay
30A POWER
Integration
Relay
100A AM1
Seat Heater
Relay (Point Side)
7.5 ALT SENCING
30A ABS No.2 Headlight
Relay
(Coil Side)
Traction Motor
Relay (Point Side)Traction Pump
and Motor Dimmer Relay
(Point Side) Ignition SW
(AM2)
Taillight
Relay (Coil Side)
15A HEAD (LH±LWR)
(CANADA)
15A HEAD (RH±LWR)
(CANADA)
Engine and
ECT ECU
15A HEAD (LH±UPR)
(CANADA)
15A HEAD (RH±UPR)
(CANADA) ABS and
Traction ECU
Battery
[LOCATION](1): J/B No. 1 (See page
20)(2): R/B No. 2 (See page 19)(3): R/B No. 4 (See page 23)
20
19 22
WhereEverybodyKnowsYourName

45
Light Control
SW
ABS and
Traction ECU
Diode
Theft Deterrent
and Door Lock ECU
Integration
Relay Noise Filter
(for Ignition
System
Injector No. 3
Injector No. 4 Igniter
7.5 ST 15A SEAT±HTR Ignition Coil
Injector No. 1
Injector No. 2
Injector No. 5
Injector No. 6
ABS
Actuator
7.5A ENGINE
15A ECU±IG
10A GAUGE 20A WIPER 20A TURN 10A HEATER 7.5A RADIO No.2
15A CIG
(4): R/B No. 6 (See page )(5): Fuse Block (F9 See page 19 )
24 19
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46
POWER SOURCE (Current Flow Chart)*1: USA
*2: CANADA
60
216
226
192178
226 90 144 134 216 102 202
208
212 90
167
A2 A15 C6 B2
B1
A10 A14 A12 A17A13 A23 A24 A25 A32 C11 B3 B4 B6 C3 C10C7
A21
Blower Resistor Auto Antenna Motor
And Relay A/C Magnetic Clutch
Alternator
A/C Control Assembly
A/C Power Transistor
A/T Indicator Light
(for Shift Lever) A/C Control SW and
Radio SWABS ECU
ABS and Traction ECUBrake Fluid Level SW
Blower Motor
Center Airbag Assembly Check Connector
Cornering Light LH
Cigarette Lighter Back±Up Light SW Buckle SW LHABS and Traction ECUCornering Light RH
190
226 22690
126
226 10168
134
144
178


* These are the page numbers of the first page on which the related system\
is shown.
The part indicated is located somewhere in the system, not necessarily o\
n the page indicated here. *Page Nos. of
Related Systems
Parts
Code or
Location
CB or Fuse
50A DEFOG
30A DOOR
30A POWER
15A STOP
15A ECU±B
10A MIR±HTR
10A HEATER
20A TURN
20A WIPER
10A GAUGE
15A ECU±IG
7.5A ENGINE
7.5A IGN
15A CIG
7.5A RADIO No.2
15A TAIL
7.5A PANEL
7.5A ST
15A TEL
10A DOME
20A RADIO No.1
25A HAZ±HORN
30A EFI
7.5 ALT SENCING
15A HEAD LH*1
15A HEAD RH*1
15A HEAD LH±LWR*2
15A HEAD RH±LWR*2
15A HEAD LH±UPR
15A HEAD RH±UPR
60A HEATER
7.5A TRAC
15A SEAT±HTR
Location
[LOCATION](1): J/B No. 1 (See page 20)(2): R/B No. 2 (See page 19)(3): R/B No. 4 (See page 23)
20
19 22
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48
POWER SOURCE (Current Flow Chart)*1: USA
*2: CANADA
D2 D3F14
D5
D4 D6 E6 D10 E1 E11 F8 F10 F4 F6
E12
E10 F7 F3
94 126
68
126
90
126
11 2
216 68 68
126
136
226
104
86
107
D11 F5 E9
E8
Engine Oil Level W arning SW
Diode
(for Parking Brake)
Diode
(for Tension Reducer)
Door Courtesy Light LHDoor Lock Motor, Door Unlock Detection
SW and Door Open Detection SW LHDay/Night Shift SWECT SolenoidECT Pattern Select SW
Engine and ECT ECU
Front Turn Signal Light RH
Fuel Lid Opener SW
Fuel Lid Opener Solenoid
*Page Nos. of
Related Systems
Parts
Code or
Location
CB or Fuse
50A DEFOG
30A DOOR
30A POWER
15A STOP
15A ECU±B
10A MIR±HTR
10A HEATER
20A TURN
20A WIPER
10A GAUGE
15A ECU±IG
7.5A ENGINE
7.5A IGN
15A CIG
7.5A RADIO No.2
15A TAIL
7.5A PANEL
7.5A ST
15A TEL
10A DOME
20A RADIO No.1
25A HAZ±HORN
30A EFI
7.5A ALT SENCING
15A HEAD LH*1
15A HEAD RH*1
15A HEAD LH±LWR*2
15A HEAD RH±LWR*2
15A HEAD LH±UPR
15A HEAD RH±UPR
60A HEATER
7.5A TRAC
15A SEAT±HTR
Location
Door Courtesy Light RH
Door Lock Motor, Door Unlock Detection
SW and Door Open Detection SW RHEngine ECU
Front Turn Signal Light LH Front Side Marker Light RH Front Side Marker Light LH Front Clearance Light RH Front Clearance Light LH
192
216


* These are the page numbers of the first page on which the related system\
is shown.
The part indicated is located somewhere in the system, not necessarily o\
n the page indicated here.
[LOCATION](1): J/B No. 1 (See page 20)(2): R/B No. 2 (See page 19)(3): R/B No. 4 (See page 23)
20
19 22
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