1991 LEXUS SC400 fuse

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
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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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50
POWER SOURCE (Current Flow Chart)*1: USA
*2: CANADA
P18
P11
N2 N4 O2 P2 O8 P4 P6 R5 R4 P20
P14
226
154
192
154
190 68 154 90
202
202
P8
P7
184 94
O5 P5 P3
Parking Brake SW
Power Window Motor RH Power Window Motor LHOil Pressure SW
Power Seat Control SW
(for Driver's Seat)
Power Seat Control SW
(for Passenger's Seat)Power Seat ECU (Passenger's)Oxygen Sensor Sub
(for California)Power Seat Motor (for Driver's
Lumbar Support Control)O/D Main SW
Radio and Player Personal LightRadio and Player (w/ CD Player)Noise Filter
(for A/C System)Power Seat Motor (for Passenger's
Reclining Control)PPS ECU
Power Window Control SW RH
Power Window Master SW and
Door Lock Control SW LH
*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
LocationP9 P12 P10 R2
Power Seat ECU (Driver's)Noise Filter
(for Defogger System)
216 126 216 208
122


* 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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52
POWER SOURCE (Current Flow Chart)*1: USA
*2: CANADA
T9 T19T11 T12
T10 W5
V3 V5 V6 W3 W2
188
11 2
194
204 200
162 216
V4 200
112 90 134 68 156
192
226 94
VSV (for EVAP) Tension Reducer
Solenoid LHTheft
Deterrent and
Door Lock ECU
Tilt and power
Telescopic ECU
Seat Heater SW (A/T)
Traction Cut SWTrip SW and
Theft Deterrent Indicator
Telephone Transceiver and
Speaker Relay
Tension Reducer
Solenoid RHVSV
(for EGR)(EX. California)
Washer Level SW Vanity Light LH
Vanity Light RH
Washer Motor
Water Temp Sender
Wiper MotorVSV (
for Water Valve)
VSV (
for Fuel Pressure Up)
*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
216
90
216
Traction ECU
Traction ECU
W1
V1 V2
T18
T16
T15
T14
T13
T8


* 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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