Page 3937 of 4087
![LEXUS SC400 1991 Service Repair Manual
92
ILLUMINATION
TAILLIGHT RELAY5±3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
C15 LIGHT CONTROL SW [COMB. SW]
3±4 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
: PARTS L LEXUS SC400 1991 Service Repair Manual
92
ILLUMINATION
TAILLIGHT RELAY5±3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
C15 LIGHT CONTROL SW [COMB. SW]
3±4 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
: PARTS L](/manual-img/36/57051/w960_57051-3936.png)
92
ILLUMINATION
TAILLIGHT RELAY5±3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
C15 LIGHT CONTROL SW [COMB. SW]
3±4 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
A1328E 828R 4A29
A1528F 926R 5B29
A2128G 128R 6C29
C1128G 228R 929
C12A28H 729T1229
C14B28I16A29T1529
C1528I16B29
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
1E20INSTRUMENT PANEL WIRE
1I
1J20COWL WIRE
1K
20COWL WIRE
3A
3C
3E22INSTRUMENT PANEL WIRE3F22INSTRUMENT PANEL WIRE
3G
3H
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IG136INSTRUMENT PANEL WIRE AND COWL WIRE (R/B NO.5)
IQ138INSTRUMENT PANEL WIRE AND CONSOLE BOX WIRE (UNDER THE INSTRUMENT PANEL CENTER)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IF36LEFT KICK PANEL
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
I1838INSTRUMENT PANEL WIREI2938CONSOLE BOX WIRE
SERVICE HINTS
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93
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94
INTERIOR LIGHT
21I
61E 91D10 1J 11F61F 21K1
4
1B
51H 10 1D61E11 1F 81H9
4
B6 IP 1
15
IP1 20
IJ IF
2 1 R
R
R
R
R
R±W
BR±W W±B
R±W
W±B
W±B
R
R R R R R
G±L
R±W
W±B
W±B
W±B
BR±W R±W
R±W
R±W
R±W
W±B
W±B
W±B
10A
GAUGE 7. 5A
RA DIO
NO. 210A
DOME
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
DIODE
DOOR OPEN
DETECTION SW RH
INTEGRATION
RELAY FADE OUT
CONTROL CIRCUIT1
R±W
D11
1
11
2
10
4
6
7 2
1D
8
B4
6 3 B4
4
1
4
1 A
1
B
1
A
2
B
3
IP 1
6
IF2
16
R±W P±B
L±W
R±W P±B
L±W
W±B
W±B
W±B
B7
(
USA )
( CA NADA )
DOOR KEY LOCK AND
UNLOCK SW LH
DOOR KEY LOCK AND
UNLOCK SW RH
DOOR OPEN
DETECTION SW LH D8 D7
D106 3
R±W
R±W
I16
,
AB
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95
B2I15
B2
B1 3A
6
3D
4
2 1 2
1 2
12
12
1
2 1
2
1
3
ON
DOOR
BX1
4
IP 1
17
Bc1
25
1
R
R
R
R
R
R±W
BR±W W±B
R±W
R±W
R±W
R
R
R
R
R
R
R
R
R
R
R
R R
R
R±W
R±W R±W R±W W±B W±B
BR±W
R±W R±W
R±W
W±B
IGNITION KEY CYLINDER
LIGHT
STEP LIGHT
PERSONAL LIGHT
VANITY LIGHT RH
VANITY LIGHT LHOPEN DOOR WARNING
LIGHT [COMB. METER]
DOOR COURTESY LIGHT
LH RH
LUGGAGE COMPARTMENT
LIGHT
1
2 A
11
B
12
I14
S11
P20
V6
V5
D5 D6
C12 , C 1 4
L6 BA
L7
LUGGAGE COMPARTMENT
LIGHT SW INTERIOR
MAP
MAP
OFF
I6
I7 B1
R
W±B
W±B
(
W/O M00N R00F )
( W/ M00N R00F )
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96
INTERIOR LIGHT
INTEGRATION RELAY (J/B NO. 1)(1B) 5±GROUND : ALWAYS APPROX. 12 VOLTS
(1D) 8±GROUND : CONTINUITY WITH FRONT LH DOOR OPEN
(1I) 6±GROUND : CONTINUITY WITH FRONT RH DOOR OPEN
D10, D11 DOOR OPEN DETECTION SW LH, RH
3±6 : CLOSED WITH DOOR OPEN
L 6 LUGGAGE COMPARTMENT LIGHT SW
1±GROUND : CLOSED WITH LUGGAGE COMPARTMENT DOOR OPEN
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C12B28D1030L 730
C14A28D1130P2032
D 530I1430S1129
D 630I16A30V 531
D 730I16B30V 631
D 830L 630
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
422LEFT KICK PANEL (J/B NO.1 LEFT)
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
1D20FRONT DOOR LH WIRE
1E20INSTRUMENT PANEL WIRE
1F20ROOF WIRE
1H
1I20COWL WIRE1J20COWL WIRE
1K
3A23INSTRUMENT PANEL WIRE3D23INSTRUMENT PANEL WIRE
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IF236ENGINE WIRE AND COWL WIRE (R/B NO. 4)
IP138FRONT DOOR RH WIRE AND COWL WIRE (RIGHT KICK PANEL)
BX140FLOOR NO. 3 WIRE AND COWL WIRE (RIGHT KICK PANEL)
Bc140FLOOR NO. 3 WIRE AND FLOOR WIRE (UNDER THE LEFT SIDE OF REAR SEAT CUSHION)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IF36LEFT KICK PANEL
IJ36RIGHT KICK PANEL
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
I 6B 240ROOF WIRE
I 738COWL WIREB 440FRONT DOOR LH WIRE
I15
38COWL WIRE
B 640FRONT DOOR RH WIREB 140ROOF WIREB 740FRONT DOOR RH WIRE
SERVICE HINTS
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2
INTRODUCTION
This manual consists of the following 11 sections:No.
SectionDescription
A
INDEXIndex of the contents of this manual.
A
INTRODUCTIONBrief explanation of each section.
BHOW TO USE
THIS MANUALInstructions on how to use this manual.
CTROUBLE±
SHOOTINGDescribes the basic inspection procedures for electrical circuits.
DABBREVIATIONSDefines the abbreviations used in this manual.
E
GLOSSARY OF
TERMS AND
SYMBOLS
Defines the symbols and functions of major parts.
FRELAY LOCATIONSShows position of the Electronic Control Unit, Relays, Relay Block, etc.\
This section is closely related to the system circuit.
GELECTRICAL
WIRING ROUTINGDescribes position of Parts Connectors, Splice points, Ground points, etc.
This section is closely related to the system circuit.
HPOWER SOURCE
(Current Flow Chart)Describes power distribution from the power supply to various electrical
loads.
INDEXIndex of the system circuits.
I
SYSTEM CIRCUITS
Electrical circuits of each system are shown from the power supply through
ground points. Wiring connections and their positions are shown and
classified by code according to the connection method. (Refer to the
section, ªHow to use this manualº).
The ªSystem Outlineº and ªService Hintsº useful for troubleshoo\
ting are also
contained in this section.
JGROUND POINTSShows ground positions of all parts described in this manual.
KOVERALL
WIRING DIAGRAMProvides circuit diagrams showing the circuit connections.
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108
LIGHT AUTO TURN OFF
1K
11
2 2
1D
8
IF
1J
1 1K
5
1B
2
2
1B
5
4
4
4 B
11
A
3A 6
B
12
1D10
6
4
2
47
3124
3
313
6
13
1
IE1
6 10A
GA UGE
10A
DOME
R±Y
W
W±B
R±W
W±B
W±B
R±GG±L W
W±LW
W±G
R±Y R±Y
W±L
R
G±W
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
BATTERY
FUSE BLOCK INTEGRATION
RE LAYTAILLIGHT
RELAY
HEADLIGHT
RELAY
FROM CORNERING
LIGHT RELAY
TO DIMMER SW
LIGHT
CONTROL SW
DOOR OPEN
DE TE CTION SW LH 120A ALT
100A AM1 60A MAIN
Q
Q S
R
R S
OFF
TAIL
HEAD
COMB INATION SW
F9
C15
D10
I16
DIODE 32 51
B
A
R±Y
7
A
4
B
10 B 13
A
5
R±Y
(CANA DA )
(
USA )
( USA )
( CANADA ) 2
I5 1
10 6
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