1991 LEXUS SC400 horn

1234
13 LEXUS SC300
4ACC
IG1
ST 1
AM1 2
1J
7 21J
5
4
1B
4 2
441H
16
8IE1
9IE1
M
1
13
4 3
265 32
14 M
21
4IE1 3IE1
6B
7A 8B 17B 14A 13A
1J
1 1K
6
IF
L
L±W L±R
R± L L
W±B
B
G± R
WW
W± L W
B±YW
B±Y
L
L±R
L±W
L
B
G±R G±R
B WW
W± B
L
G±O G±O L
W±B
W± B
20A
WI PER
25A
HAZ±HORN
I15
IGNITION SW
40A
IGSW
60A MAIN 100A AM1
120A ALTF9
FUSE BLOCK HORN
RE LA Y
C15
HORN SW
[ COMB. SW]
To Thef t Deter rent and
Door Loc k ECU< 17±3>
11
HORN
H5
LH
H6
RH
BATTERY W5
WIPER MOTOR
WIPER RELAY
OFF
MIST
INT
LOW
HIGH
WASHER
INTTIME
+2 +1 S B B1 I N1 IN2 W E
WIPER AND WASHER SW
[COMB. SW] W2
WASHER
MOTOR
Power
Source
Wiper and Washer
B
6 74 WIPER AND WASHER SW
[COMB. SW]
C15B
,C16 A
C15
B
C1 6A
Horn
1
10 11 12 13 17 189
8
4
3
2 567
14 15 16 12
89
10 11 12 13 147
6
5
4
3
Left kick panel
5 6
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OVERALL ELECTRICAL WIRING DIAGRAM
1234
17 LEXUS SC300 (
Cont . ne xt pa ge )
4 ACC
IG1
ST1
AM1 3
2
1J
7 1B
21J 51J822
1B
51E 11
1E
51K 7 1K
13 1I 14 22
1H
10
1B
4
1
4 9IJ1 4IJ19IE1
8BY1 8 BT1 14 IE1 7 BT1 9 IP1 17 IG1 15 IF2 14 IF2 1 2
8A +B 2 2A
IG 7B
ACC 4B
SH 20 A
+B1 5B
HE AD 13 B
TAI L 1A
SRLY 11 B
HORN 8B
DS WP
10 B DS WL
12 B DSWH
1B LUG
5ATO
19 ATSW
6AKSW
14 AL1
10 AUL 3
3 1 2
1 1
2
2
1 1
BL BM EA IF 3F
7
3A
1
18
1E 10
1D
1
1J
16 A
E
15 AUL 1
18 A UL2
17 A LSWP
5IF2 4IF2 5IP1 14IP1 8IP1 19IP1 12 A
PCTY 7A
LSWP 4A
ACT+ 3A
ACT± 11 A
LSWD 13 A
DS WD
LOCK
UNLOCK
IJ
IF 20 IP12
31
1
3
2
LOCK
UNLOCK
1
2
8
LOCK
UNLOCK
1
3
2
LOCK
UNLOCK
G±W G± Y Y
R±B
W± L L±W L±R
P± B
R± W R
G±Y G±W
W±B
W±B
W± B
W± B
W± B G± Y
R± B G±L
W
R
R±Y
G±W L±O
G±R Y±R
R± W P± B
L±R
L±W
W± L R±B R
W
B±O
L±R
B±R
L±W L±W
W
W
W
R W
W± L
W
W± L
W± L
W
L±R
L±G
G±L
R±W
B
W±B
L
Y G±Y
G
R±B G±L
G±Y
G±W
G±W G± YG± L
R±B G± L
R±B G
G± Y
W±B
W± B W± B W± B
R
W±B
W±B
W± B
W± B W±B
R± L
B±Y
B±O
4 1
3 2
60A MAIN
100A AM1
120A ALT
40A
IGSW
F9
FUSE BL OCK I15
IGNITION SW
30A
DOOR
15A
ECU±
IG15A
CI G
25A
HAZ±HORN 10A
DOME
T1
THEFT DET ERRENT
HORN
THEFT DETERRENT AND DOOR LOCK ECU
F10
FUEL LID
OPENER SW
L±R
L±G
G± L
R± W
B
L
BATTERY
F14
FUEL LID OPENER
SOLENOID
L5
LUGGAGE COMPARTMENT
KEY UNLOCK SW E5
ENGI NE HOOD
COURTE SY SW
To Luggage Compartment
Light SW< 6±3> L4
LUGGAGE COMPARTMENT
DOOR OPENER MOT OR
L1
LUGGAGE COMPARTMENT
DOOR OPENER SW
To UNLOCK WARNING SW
<4±4><5±4>D7
DOORKEYLOCKAND
UNLOCK SW LH
P5
DOOR LOCK CONT ROL S W LH
[ POWER WI NDOW MASTER SW] Fr om Headlight Relay
<4±2><5±3>
From Taillight Relay
<4±3><5±3>
Fr om Sterter Relay
<1±3><2±2>
Fr om Hor n Rel ay
< 13±1>
To Power Main Relay
< 12±4>
D9
DOOR LOCK CONT RL
SW RH
D8
DOORKEYLOCKAND
UNLOCK SW RH
Power
Source Theft Deterrent and Door Lock Control
W± L
B±YR± L
6 2
7 T8 B , T9 A
Fr om Tilt and Power
Telesc opic ECU< 11±1>
Y
Under the center
pillar RH Ba ck
panel
centerFro nt si d e of
right fender
Lef t kic k panel
Left k ick panel Right k ick
panel
R± B
M6
5
5
6
2IG19A
To Trip SW and
Theft Deterr ent
I ndic ator Light
< 21±4>
G± B G± BIND
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244
Rear Window Defogger
and Mirror Heater
Remote Control Mirror
Seat Heater
Shift Lock
SRS AIRBAG
Starting
Taillight and
Stop Light
Theft Deterrent and
Door Lock Control
Turn Signal and Hazard
Warning Light
Wiper and Washer
Wireless Door Lock
Remote Control
Horn
Ignition
Illumination
Interior Light
Liquid Crystal Inner
Rear View Mirror
Moon Roof
Power Seat
(Driver's)
Power Source
Power Window
PPS (Progressive
Power Steering
Radio and Player
ABS and
Traction Control
Automatic
Air Conditioner
Auto Antenna
Back±Up Light
Cellular Mobile
Telephone
Charging
Cigarette Lighter
Combination Meter
Cruise Control
Headlight and Light Auto
Turn Off (for USA)
Headlight
(for Canada) ECT and
A/T Indicator
4±2 16±2 7±2
3±2 21±2 3±8
14±4
18±2 19±4 (w/o CD Player)
20±8 (w/ CD Player)9±2 8±2
4±7 (for USA)
5±7 (for Canada)11±2
12±311±5 (w/ Driving
Position Memory)11±7 12±1 1±5 13±2
6±2 15±2 14±2
13±2
17±7 7±3 17±2 15±3
1±315±2
Power Tilt and
Power Telescopic12±2
Power Seat (Passengerºs
and Electric Tension Header
5±2 2±2
Cornering Light ABS (Anti±Lock
Brake System)
22±2
Engine Control Unlock and Seat
Belt Warning
1±2
23±2 (w/o Driving
Position Memory)
1 23±119±2 (w/o CD Player
20±2 (w/ CD Player
14±310±2 (w/ Memory)
5±7 (w/o Memory)
4±3 (for USA)
5±3 (for Canada) 4±5 (for USA)
5±5 (for Canada)
OVERALL ELECTRICAL WIRING DIAGRAM
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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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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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47
216182
216
178
216
129 104 144 10260
90
216 62
68
11 2
148
104
111 200 148 148 190
D1
C16 C24
C15 C19 C23 C22
C12
C13
C14C14
C13
C12
Airbag W arning Light
Charge Warning Light
Dimmer SW [Comb. SW]Cruise Control Indicator Light
[Comb. Meter]A/T Indicator Light
[Comb. Meter]
Combination Meter
Rear Lights Warning Light Turn Signal Indicator Light
[Comb. Meter] High Beam Indicator Light
[Comb. Meter]
Check Engine Warning Light
Open Door Warning Light
Traction Indicator Light
ABS Warning Light
[Comb. Meter] Seat Belt Warning LightABS Warning Light and T raction
Off Indicator Light [Comb. Meter]
Coolant Level Warning LightCruise Control ECU Turn Signal SW
[Comb. SW]
Wiper and Washer SW
[Comb. SW]
Choke Coil
Crutch Start SW
Cruise Control Clutch SW
Diode (for Brake Fluid Level)Light Control SW
[Comb. SW] Horn SW [Comb. SW]Combination MeterCornering Light SW
[Comb. SW]
C12 80
82
216
216 216 98
86
216134
216
216 216 184
216
80
90
102 80
90
102
68
94
134
148
216
(4)
: R/B No. 5 (See page ) 22
WhereEverybodyKnowsYourName

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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49
F16 F18 I1H8
G2
G1 H1 H3 H2 H4 H5 I2 I14 I15 L7 I16 L2 M2L6
L3 M4
80
194
111 94 101
62
68
101 11 2
126
186 154
162
68 68 94
216
90 86
107
H6 H7 H9 98
N1
Unlock Warning SW
[Ignition SW] Igniter No.1 Fuel Pump ECU
Glove Box Light
Headlight LH HI
Hazard SW
High Mount Stop Light
(w/ Rear Spailer) Horn LHISC ValveIgnition Key Cylinder Light
Key Inter Lock Solenoid
Moon Roof Control Relay Light Failure Sensor
Luggage Compartment
Light SW
A/T Indicator SW
Back±Up Light SW
Neutral Start SW Licence Plate Light Integration Relay Fuel Sender
Glove Box Light SW
Headlight RH HI
Headlight LH LO
Headlight RH LO
Horn RH
High Mount Stop Light
(w/o Rear Spailer)
Luggage Compartment
Light SW
Moon Roof Motor
86
98
108
182
216
82
91
94
102
82
216 90
104
(4)
: R/B No. 5 (See page ) 22
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