LEXUS SC400 1991 Service Repair Manual

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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98
STOP LIGHT
1I
10
1C
21E 12
3D
13
1C
10 1H
1 3A
4
1 2
B10 B15
+
±
+
±
BM BL
B15 B14
Bd1
2 Bc1
11
Bd1
1
Bc1
7
7
84
33 4 1
11
1
2
55 1 2
W±B W±B W±B G±W
G±W
W
G±W
G±W
G±W
Y
V±G Y
Y
Y
G±W
G±W B
W±B
R±W
R±W R±W
W±B
W±B
W±B B
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
15A
STOP 10A
GA UGE
A
1
B
11
HOLD
CIRCUIT
W±B
STOP LIGHT
[REAR COMB. LIGHT]
LH RH
R10 R11
HIGH MOUNT STOP
LIGHT
(
W/O REAR SPOILER )
H8
HIGH MOUNT STOP
LIGHT (
W/ REAR SPOILER )
H9
LIGHT FAILURE SENSOR L3 C14 , C1 3
AB
BU1
9
V±G
STOP LIGHT
SW S12
REA R LIGHT WARNING
LIGHT [COMB. METER]
B21
W±B
W±B
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99
CURRENT IS APPLIED AT ALL TIMES THROUGH A STOP FUSE TO TERMINAL 2 OF THE STOP LIGHT SW.
WHEN THE IGNITION SW IS TURNED ON, CURRENT FLOWS FROM THE GAUGE FUSE TO TERMINAL 8 OF THE LIGHT FAILURE
SENSOR, AND ALSO FLOWS THROUGH THE REAR LIGHT WARNING LIGHT TO TERMINAL 4 OF THE LIGHT FAILURE SENSOR.
STOP LIGHT DISCONNECTION WARNING
WHEN THE IGNITION SW IS TURNED ON AND THE BRAKE PEDAL IS PRESSED (STOP LIGHT SW ON), IF THE STOP LIGHT CIRCUIT IS
OPEN, THE CURRENT FLOWING FROM TERMINAL 7 OF THE LIGHT FAILURE SENSOR TO TERMINALS 1, 2 CHANGES, SO THE LIGHT
FAILURE SENSOR DETECTS THE DISCONNECTION AND THE WARNING CIRCUIT OF THE LIGHT FAILURE SENSOR IS ACTIVATED.
AS A RESULT, THE CURRENT FLOWS FROM TERMINAL 4 OF THE LIGHT FAILURE SENSOR " TERMINAL 11 " GROUND AND TURNS
THE REAR LIGHT WARNING LIGHT ON. BY PRESSING THE BRAKE PEDAL, THE CURRENT FLOWING TO TERMINAL 8 OF THE LIGHT
FAILURE SENSOR KEEPS THE WARNING CIRCUIT ON HOLD AND THE WARNING LIGHT ON UNTIL THE IGNITION SW IS TURNED OFF.
S12 STOP LIGHT SW
2±1: CLOSED WITH BRAKE PEDAL DEPRESSED
L 3 LIGHT FAILURE SENSOR
1, 2, 7±GROUND : APPROX. 12 VOLTS WITH STOP LIGHT SW ON
4, 8±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
11±GROUND : ALWAYS CONTINUITY
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C13B28H 930R1131
C14A28L 330S1229
H 830R1031
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1C20FLOOR WIRE
1E20INSTRUMENT PANEL WIRE
1H20COWL WIRE1I20COWL WIRE
3A22INSTRUMENT PANEL WIRE3D22INSTRUMENT PANEL WIRE
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
BU140FLOOR WIRE AND INSTRUMENT PANEL WIRE (LEFT KICK PANEL)
Bc140FLOOR NO. 3 WIRE AND FLOOR WIRE (UNDER THE LEFT SIDE OF REAR SEAT CUSHION)
Bd140FLOOR NO. 3 WIRE AND LUGGAGE NO. 2 WIRE (RIGHT SIDE OF LUGGAGE COMPARTMENT)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
BL40UNDER THE CENTER PILLAR RH
BM40BACK PANEL CENTER
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
B1040FLOOR MAIN WIREB1540FLOOR MAIN WIRE
B1440FLOOR MAIN WIREB2140FLOOR NO. 3 WIRE
SYSTEM OUTLINE
SERVICE HINTS
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100
STOP LIGHT
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86
TAILLIGHT
1K
5 1K
11
1A
31C 16
1J
1 1 2
1
2
E11
E5
1B
2
OFF
TAI L
HEAD
IF G
G
W±B
W±B G
W
W±B W±B G±L LG±BG±W
G±W
G
G
G
G G
W±B
W±B
W±L
4 3103
411
TAILLIGHT
RELAY
FUSE BLOCK COMB INATION
SW
BATTERY
INTEGRATION
RELAY
INTEGRATION
RELAY
15A
TAIL
LIGHT
CONTROL SW
(USA )
( CANADA )
120A ALT
100A AM1
C15
I16
(
CANADA )
I16
(
USA )
W±L
F9 15
23
6 4
(
USA )
( CA NADA )
2
1
FRONT SIDE MARKER
LIGHT LH
F5
FRONT CLEARANCE
LIGHT LH F3
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EABM
E4 B15 B15
B14
B14
1 2 1
2 1C
21E 12
3D
13 3A
4
B
11 A
1
G
G
W±B GG
W±B W±B
Y
Y
V±G
V±G YY
G
G G
W±B
W±B
W±B
W±B G±R G±R
W±B
W±B W±B G G
911
384
111
255
G±R
W±B FRONT CLEARANCE
LIGHT RH
LIGHT FAILURE
SENSOR
10A
GAUGE
REAR LIGHT
WARNING LIGHT
[COMB. METER]
TAI L LI GHT
[REAR COMB. LIGHT]
LICENCE PLATE
LIGHT
L3
L2
R11
R10
RH
LH FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
HOLD
CIRCUIT
BU1
9
C13 ,
C14
B A
+
±
FRONT SI DE M ARK ER
LIGHT RHF6
F4
E1
E1
B
+PK
±PK WRN
W±B
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88
TAILLIGHT
WHEN THE LIGHT CONTROL SW IS TURNED TO TAIL OR HEAD POSITION. THE CURRENT FLOWS TO TERMINAL 3 OF THE LIGHT
FAILURE SENSOR THROUGH THE TAIL FUSE.
WHEN THE IGNITION SW IS TURNED ON, THE CURRENT FLOWS FROM THE GAUGE FUSE TO TERMINAL 8 OF THE LIGHT FAILURE
SENSOR, AND ALSO FLOWS THROUGH THE REAR LIGHT WARNING LIGHT TO TERMINAL 4 OF THE LIGHT FAILURE SENSOR.
TAILLIGHT DISCONNECTION WARNING
WITH THE IGNITION SW ON AND THE LIGHT CONTROL SW TURNED TO TAIL OR HEAD POSITION. IF THE TAILLIGHT CIRCUIT IS
OPEN, THE LIGHT FAILURE SENSOR DETECTS THE FAILURE BY THE CHANGE IN CURRENT FLOWING FROM TERMINAL 3 OF THE
LIGHT FAILURE SENSOR TO TERMINAL 9, 11 AND THE WARNING CIRCUIT OF THE LIGHT FAILURE SENSOR IS ACTIVATED.
AS A RESULT, THE CURRENT FLOWS FROM TERMINAL 4 OF THE LIGHT FAILURE SENSOR " TERMINAL 11 " GROUND AND TURNS
THE REAR LIGHT WARNING LIGHT ON, WHICH REMAINS ON UNTIL THE LIGHT CONTROL SW IS TURNED O\
FF.
TAILLIGHT RELAY
5±3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
L 3 LIGHT FAILURE SENSOR
4, 8±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
3±GROUND : APPROX. 12 VOLTS WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
11±GROUND : ALWAYS CONTINUITY
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C13B28F 526L 230
C14A28F 626L 330
C1528F 926R1031
F 326I16A29 (USA)R1131
F 426I16B29 (CANADA)
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1A20ENGINE ROOM MAIN WIRE1B20ENGINE ROOM MAIN WIRE
1C20FLOOR WIRE
1E20INSTRUMENT PANEL WIRE
1J20COWL WIRE1K20COWL WIRE
3A22INSTRUMENT PANEL WIRE3D22INSTRUMENT PANEL WIRE
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
BU140FLOOR WIRE AND INSTRUMENT PANEL WIRE (LEFT KICK PANEL)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
EA34FRONT SIDE OF RIGHT FENDER
IF36LEFT KICK PANEL
BM40BACK PANEL CENTER
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
E 1E1134ENGINE ROOM MAIN WIRE
E 434ENGINE ROOM MAIN WIREB1440FLOOR MAIN WIREE 534ENGINE ROOM MAIN WIREB1540FLOOR MAIN WIRE
SYSTEM OUTLINE
SERVICE HINTS
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11 2
THEFT DETERRENT AND DOOR LOCK CONTROL
2
1I
14
1K
13
1K
11 2
3A
1
1J
1
1B
22
1H
13 3F
7
1E
18 1I
16 4
4
1D
8 1H
10 1B
5
1D 10 I8
I11
I11
B4
9
10
1 2IE1
6
IG1
17 IF2 15 IF214
IF2
16 IF2 18 IF2 5IF24
IF2
7
B
13
TAIL B
5
HE AD A
2
IG B
7
ACC A
20
+B1
A
16 E
A
6 KSW
A
19 TSW
A
14 L1
A
10 UL3
A
13 DSWD
A
11 LSWD
A
17 L2
A
18 UL2
1
13
6 4
7 24
2
31
8
21
IF 2 1
M
64 5 31 2
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
60A MAIN
120A ALT
100A AM1
LOCK
UNLOCK
LOCK
UNLOCK
15A
ECU±IG 15A
CIG10A
DOME
HEA DLIGHT
RELAY
G±Y
G±Y
G±L
R±B
L±W
L±R
W±B
W±B
W±B
W±L W
W
B±RL±R R
R
R±Y
G±W
W±B
Y
L
G±Y G G±Y
R±B
W±L
R±BG± L
R±B
G±L
L±W
L±W
R±W
L±W
L±W
R±BG±L
W±B L±R
W±B W±B W±B
G
G±Y L
W±B
W±B W±B
R±YTAI L LI GHT
RELAY
W±LW
TO FUSE º 15A TAILº
THEFT DETERRENT AND DOOR LOCK ECU
UNLOCK WA RNING SW
[IGNITION SW]
LUGGAGE COMPARTMENT
DOOR OPENER SW
DOOR KEY LOCK AND
UNLOCK SW LH
DOOR LOCK MOTOR,
DOOR UNLOCK DETE CTION AND
DOOR OPEN DETECTION SW LH
POWERWINDOWMASTERAND
DOOR LOCK CONTROL SW LH
FUSE BLOCK
L±R
BATTERY
F9
I15
L1
D7
D10
P5
T8 , T9 B A
DIODE
32 51 2
W±B
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