Starter LEXUS SC400 1991 Service Repair Manual

OVERALL ELECTRICAL WIRING DIAGRAM
1234
1 LEXUS SC300 (
Cont . ne xt pa ge )
2 1
5
3
1J
7 1J
31J 5
3D
1
1B
4 1E
81H 52 2
3D
2
16 IE1
1EB2 15 IE1 3EB1
2
5IJ2 13IJ2 2EB2
1A B B
B
B
L
IG
S 1J
6
1K
4
1
C
1
D
4
ACC
IG1
ST1
IG2
AM1 2
1
6
11 AM2
15 14 2
2
2
1IG3
W
W± R B±Y
B±W
B± O
Y± G
B±YW
B
W± L
W
W± R
W± R
B
W
B±Y W
B
B B
B± W L±O
B B±O
B
B±W
Y± G
Y±G
Y±G
B± Y
W
B
B L±O
Y±G
B
W± R
4 7 9 14 13 5
6
120A ALT
100A AM1 30A I NJ
30A AM2
60A MAIN
F9
FUSE BL OCK
40A I GSW
I15
IGNITION SW
C12
CHARGE WARNING
LIGHT 7. 5A
ENGINE
7. 5A
AL T
SENCI NG
To Integr ation
Relay< 5±4> STARTER
RELAY
7. 5A
ST
N1
NEUTRAL
START SW
To Theft Deterrent
and Door Lock ECU
< 18±3>
To Engine and
ECT ECU< 2±2>
STARTER
AL TERNATOR
BATTERY
2
3
1
Charging Starting
B± O
Y± G
3
4
S6 D , S7 C
(Canada )
12
11
6IJ1
A1 0 B , A11 A 1
23 1
BA
A1 0 A11 BL ACKALTERNATOR 1
1
D
C
START ER
S6
S7 BROWN
Power Source
Y± G
2 1
IJ2 8B B
B± WB±W
(A/ T )
(
A/T )
(M/T )
(
M/T )
B C2 3
CL UTCH
START SW
B
2
3
P
N
B±O
B±O
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OVERALL ELECTRICAL WIRING DIAGRAM
1234
1J
7 1J
31J 6 22
1B
4 1I
51K 42 22
22
2
4
ACC
IG1
ST1 IG2
AM1 2
1
6
11 AM2
32
41 3 1
4
2
21
21
21
21
16 IE1
15 IE1 1 EB22
1BT1 2BT1 3BT1
N P
2
3
21
413
6 14
7
9 17 BT1
21 21 BK EB1J
5
1E
12 7
8
4
15
12
13 1
814 25
1
7IJ2 9IK2 IK1
3A
4
3D
13
3B 1A IK1
IK1
2 1 M 3
W
W±R
W± R W
B± Y
B±R B±R B± Y B±Y
B± R
B± R
L±Y
G±W
B±W
B±O
B±O
L±RW
B±R B±Y B
Y
B±O
B±O
B±O
B±O
B±O
B±O
GR ±YB±R B± Y
B± O
G
G
B
L±O
L±O B
R±GP
G
G
W± B GP
R± G
W± B
W± B L±Y
G±W
YY W±B
B±R
B±YB±W
B± W
W± R
B±O B±O
B±O
B± O
B±O
W
W± B
B±R3 4
G±W W± L
LG
B±Y
B±W
G± R G±Y LG
L±Y
B±R
G± Y
G±R
LG
GR±Y
B± O
B±W B± O
B±R
B±RB± Y
R±G L±Y
G±W B
Y
B
B± Y
B±R W
L±R
B± Y LG
GR±Y
R±L
W
TE1 TE2 TT
ENG
OX 2 OX 1VF1
FP +B
5
G
3
B
W
T6TDCL
C3
CHECK CONNE CT OR
E1
CHECK ENGINE WARNI NG
LIGHT[ COMB. METER]
10A
GA UGE
EFI
MAIN
RELAY
30A
EFI
N1
NE UT RA L
ST ART SW
ST ARTER
RE LA Y
F1 6
FUEL PUMP ECU
BATTERY
F15
FUEL PUMP
30A AM2
60A MAIN
120A ALT
100A AM1
30A I NJ
I11
I NJECTOR No. 6 I10
I NJECTOR No. 5 I9
I NJECTOR No. 4 I7
I NJECTOR No. 2 I8
I NJECTOR No. 3 I6
I NJECTOR No. 1
From Starter< 1±3>
To Thef t Deter rent
and Door Loc k ECU
< 17±3> F9
FUSE BL OCK
7. 5A
ST
7. 5A
IGN
40A
IGSW I15
IGNITION SW
Engine Control
2 LEXUS SC300
GR±YB±R
VF2
TE1
W
W± B
B±Y
17 18
1 2345 6789 10
23
22
21
20
19
15
14
13
12
11 16 12 34 56 78
9 10 1112 13 14 1516 1718
AB
CHECK E NGI NE WA RNI NG
LIGHT[COMB. METER] W
C14 C13 6IJ1
1EB2
IJ112
B±R
B± R
E1
3 BR
25
From Stop Light SW
<5±6><4±6>
C1 3
IG±
From Igniter
ºTACº<1±5>
B,C14 A
19
P
BR
1IJ1 IK1
4
3B
4
Power
Source
(
Cont . ne xt pa ge )
Fr om A/C Contr ol
Assembly
< 22±7> < 22±5>
TC A/ C
P±B P±L4
11
11TC
Fr om A/C Contr ol
Assembly< 22±8> P± B G± Y
IG3
3
B±R
Under the center
pillar LH Fro nt s i de o f
left f ender
7
4
2 1IJ28
B B±W
B
C23
CLUTCH
START SW (
A/T )(
M/ T )
7IJ1
3IJ1B±O B±O
(A/ T )
3 EB1B (
M/T )
*1: (
w/ Traction Control )
* 2:
(
w/oTractionControl )
* 3: (
USA Spec. )
* 4:
(
Ex. USA Sp ec. )
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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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53
118 10422662
68
11 2
208
212
226 102
94
W7 W8 W10
Wireless Door Lock
Main SW
Wireless Door Lock ECU
Woofer Speaker Amplifier
Power Main Relay
A/C Magnetic Clutch Relay
EFI Main Relay
Heater Relay
Defogger Relay
Turn Signal Flasher
Horn Relay Diode
Cornering Light Relay Starter Relay
11 2
194 68
126 190
226
102
111
11 2
Diode
(4): R/B No. 5 (See page )
22
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57
87
65
43
21
10 9
12 11
14 13
21
22 21
20 19
18 17
16 15
2
2
2
2
2
2
2
2
2
2
2 2 22
2
2
2
2
2
22
2 2
2
IF 4
1B
1
4
4 2
2
4
4
EB1
3
W
B
B
B
B±R R±L
B
B
L±O R±Y L±R
WR
B±Y W
L±Y
W±L R
R
R
R±G R±B
R±W
B
R±Y
B
B
B±R
2
B
W±B B
R
1
212
1 2
2
4
3
1
1
3 43
1
3
5
2
2
4 4
3
5
3
4
20A RADIO NO. 1
25A HAZ±HORN 30A EFI
10A DOME
15A TEL
7. 5A ALT SENCING 7. 5A TRAC
HEADLIGHT
RELAY STARTER
RELAY
60A HEATER
50A DEFOGGER DEFOGGER
RE LA Y
15A SEAT±HTR
15A HEAD
(
LH±UPR )
15A HEAD (
RH±UPR )
15A HEAD (
LH )(
FOR USA )
15A HEAD (
LH±LWR )(
FOR CANADA )
15A HEAD (
RH )(
FOR USA )
15A HEAD (
RH±LWR )(
FOR CANADA )
DIMMER
RELAY
SEAT HEATER
RELAY 10A MIR±HTR
W±B I1W±B
B
(
M/T )
( A/T )
( CA NA DA )
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62
STARTING AND IGNITION
AM1
AM2
11 4
1
6
ST1
IG2
A
1
B 1 1J
6
1J
7
2
22
1B
4 1K
4
6 9 4 14 13 7 M
IE1
16
EB2
1 IE1
15
E19
L±O
L±O B
B
B WW±R
W± RW
W±L
W±RW±L W
W
B±O
B±W
B
B
B
B
W± R
BATTERY
STARTER
31
52
IGNITION SW
40A
IGSW
STARTER
RELAY 7. 5A
ST
FUSE BLOCK
TO THEFT DETERRENT AND
DOOR LOCK ECU 30A AM2
120A ALT
100A AM1
30A INJ
60A MAIN
I15
S6 , S7
F9
BA
3
4
2 1
2
3 IJ1
6
EB1
3
IJ28
IJ1
7
B±O
B
B
B
BB±W B±W
B±W
(A/T )
( M/T )
NEUTRAL
START SW CLUTCH
START SW
N1 C23
( A/T )
( M/T )
2
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64
STARTING AND IGNITION
C 4 COLD START INJECTOR
2±1 : APPROX. 12 VOLTS WHILE START INJECTOR TIME SW IS CLOSED AND STARTER CRANKING
I15 IGNITION SW
4±1 : CLOSED WITH IGNITION SW AT ST POSITION
11±6: CLOSED WITH IGNITION SW AT ON OR ST POSITION
N 1 NEUTRAL START SW
3±2 : CLOSED WITH A/T SHIFT LEVER IN P OR N POSITION
S 6(B), S 7(A) STARTER
POINTS CLOSED WITH NEUTRAL START SW ON AND IGNITION SW AT ST POSITION
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C 326F 926N 327
C2328I 227S 6B27
D1326I 427S 7A27
E1028I1529
E1228N 127
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
1J20COWL WIRE1K20COWL WIRE
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
EB134ENGINE WIRE AND ENGINE ROOM MAIN WIRE (FRONT SIDE OF R/B NO 2)EB234ENGINE WIRE AND ENGINE ROOM MAIN WIRE (FRONT SIDE OF R/B NO. 2)
IE136ENGINE ROOM MAIN WIRE AND COWL WIRE (R/B NO. 4)
IJ136ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)
IJ236ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
ED34REAR SIDE OF INTAKE MANIFOLD
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
E1434ENGINE WIREE1934ENGINE WIREE1834ENGINE WIREE2034ENGINE WIRE
SERVICE HINTS
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11 3
M
64 5 31 2
1K
4
2
2
2 2
I11
B7 B7 I11
EB1
3 IE1
15
IP1
20
IP1
8IP1 19
IP 1
15 IP1 6IP1 18 IP1 5IP114 IE 1
14 BT1 9
IP1
7
A
15 UL1
A
12 DSWP
A
7 LSW P
A
3 ACT±
A
4 ACT+
B
12 DS WH
A
5 TOA
1
SRLY25 13
2
31
2
31
IJ EA
2 1
PRND 2 L
146578 9
GR
R±B
L
G±W G
W
A/T INDICATOR SW
[NEUTRAL START SW AND BACK±UP LIGHT SW]
N1
2
3
FROM POWER SOYURCE SYSTEM
(
SEE PAGE 56 )
7. 5A
ST
P
N STARTER
RE LA Y
THEFT DETERRENT AND DOOR LOCK ECU
LOCK
UNLOCK
LOCK
UNLOCK
DOOR KEY LOCK AND
UNLOCK SW RH
DOOR LOCK MOTOR,
DOOR UNLOCK DETE CTION AND
DOOR OPEN DETECTION SW RH DOOR LOCK
CONTROL SW RHENGINE HOOD
COURTESY SW
LUGGAGE COMPARTMENT
DOOR OPENER MOTOR
G± Y G±L
R±B
L±W
L±R W±B
L±R L±R B
Y
W
B
L±O B
B
L±O
B
G±L L±R
G±L B
W±B W±B
L±R
W±B W±B W±B
W±B W±B
L±R R±BG±L
L±W
P±B
R±W G±W
G±Y G±Y
G±W
R±W P±B
L±W
R±BG±L L±W
P±B
R±W
G±W
L4 E5
D9
D11 D8
T8
,T
9
B A
M
1
IJ1
6
B±W
( A/T )
IJ28
B±W B
( M/T )(
M/T)
B±W
( A/T )
B±W
( M/T )
CLUTCH STA RT
SW (
M/T )
C23
( A/T )
B3 3
W±BW±B
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