1991 LEXUS SC400 Service Repair Manual

Page 3985 of 4087

LEXUS SC400 1991  Service Repair Manual 
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

Page 3986 of 4087

LEXUS SC400 1991  Service Repair Manual 
567 8
22 LEXUS SC300(
Cont  d )
12
II1
7
II1 2 IR2
5
IR2 4
IR2
IR1
IR1
IR1
IR1
IR2
IR2
IR2
IR2 1J
82
1E
22
5
1B
3A 3A
3A
3E
3H 3G 3B
3G
11
1E
IQ1
IQ1 IQ1 IQ1 IQ1 IQ1 II1
5
IR2
IR1
IR1
IR1
IN1
4
EB1

Page 3987 of 4087

LEXUS SC400 1991  Service Repair Manual 
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

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LEXUS SC400 1991  Service Repair Manual 
242
HOW TO READ THIS SECTION
OVERALL ELECTRICAL WIRING DIAGRAM 
WhereEverybodyKnowsYourName

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LEXUS SC400 1991  Service Repair Manual 
Junction  Block (the number in the circle is the
J/B No. and connector code is shown beside
it).  Junction Blocks are shaded to clearly 
separate them from other parts (different
junction blocks are

Page 3990 of 4087

LEXUS SC400 1991  Service Repair Manual 
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
Warni

Page 3991 of 4087

LEXUS SC400 1991  Service Repair Manual 
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.
T

Page 3992 of 4087

LEXUS SC400 1991  Service Repair Manual 
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 Ignit