engine LEXUS SC400 1991 Service Repair Manual

70
ENGINE CONTROL
I22E18
E17
A
2
SP1 A
33
BATT B
76
NSW A
32
+B1 A
31
+B
A
6 W
A
4 STP
B
77 STA
B
20 #10
B
18 #30
B
15 #60
B
19 #20
B
58 IGF
B
57 IGT
A
1
IGSW
B
3
A
10
A
1A 15 A13 A 14
54
12
IJ2
11
EB1
4
IG2
7
IK2
9
IJ2
3
3A
4
3D
13
+B TACHIGF IGT
B±R
B±O B±O
L±R B Y
B
G±W R
L±R Y
B±Y
B±W
B±R
B±O
BB
L±Y
IH L±Y
L±Y
BR
L±Y
W±YR±YB±Y
L±R B Y
B
G±W L±Y
B
W±L
B
L±Y
BR
Y
R
L±R
PP
P
B±Y
B±W
B±OB±R
B±R B±Y
B±O
CHECK ENGINE
COMBINATION METER
ENGINE ECU
(
M/T )
IGNITERTO TACHO METER
E11 , E1 2AB
I2
C13 , C 1 4
A
B I33
B
34 B 32 B 35 B33
E15
B
16
A
24 B
17
B±Y W B±R
B±R
B±R
G±Y V±R
L±W
LG±B
B±R
B±R
1346 25
ISC VALVE
I1
ISC2 ISC4 ISC1 ISC3
#40
#50
M±REL
B±R B±O
W
C±
3
B±O
FROM IGNITION
CO IL
ENGINE AND ECT ECU (
A/T )
E9 , E10
AB
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71
*1 :W/TRACTIONCONTROL
* 2 : W/O TRACTION CONTROL
BK
I22 B12
5
1
2
34
M
21
A
21 DI
A
22 FPC B
46
THG B
44
THW
2 1
2
1
BT1
2BT1 1
FPC DI E FP +B
B
L±Y
B±R
B±R
B±R
BR BR
G
L±Y
B±R
W±B G
B±R P
R±G P
R±G P
R±G
G
W±B
G
W±B W±B
B±RG EGR GAS TEMP. SENSOR
(
FOR CALIFORNIA )
EFI WATER TEMP. SENSOR
ENGINE ECU (
M/T )
FUEL PUMP ECU
FUEL PUMP
F15 F16 E11
,E1 2
E3
E4
A
B
IJ1
8IJ1 14
2 1
1 2 1 1H
41K 10
44
4IJ111
11 EC ED
E18 E20
I32I33
B
49
B
50 B 26 B27
B
7
B
25 B 80 B79
A
15
B
75 B 74 B 39 R±Y R±Y
B±R
BR
W±B
W±B BR
W
W
RY
B
L G
L±R
G±R
G±B
B±W B±R
B±RB±RB±R
B±R
2
( *2 )
(*2 )
(*1 )
( *1 )
VSV
(
FOR EGR )
VSV (
FOR EVAP )
VSV
( FOR INTAKE
CONTROL VALVE )
V1
V2
V3
10A
MIR
HTR
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
(
FOR USA SPEC. )(
FOR USA SPEC.)
(
SHIELDED )
( SHIELDED )
KNOCK SENSOR NO. 2
( ON REAR SIDE )
KNOCK SENSOR NO. 1
(
ON FRONT SIDE )
K1
K2
(SHIELDED )
2341
KNK1 KNK2 G1 G2 G± NE
G1 G2 G± NE
B
EO1 EO2
DISTRIBUTOR
D13
EGR EVAP ACIS
ELS
15A
TAIL
ENGINE AND ECT ECU (
A/T )
E9 , E10
AB 2
13
B±R
B±R
DIODE
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72
ENGINE CONTROL
VC
VTA
IDL
E2
2
134
12 34
E20 E18 E18
B
42
VTA2 B
63
IDL2 B
65
E2 B
64
IDL1 B
43
VTA1 B
41
VC B
45
THA B
66
KS
A
35 PS
B
47 OX2 5
THA KS VC
E2
BR BR
B±R
B±R
WGB
L±Y
B±R
BR
BR
BR
BR
BR R
Y
L±R
BR
Y±B
Y±G L±R
BR
R
Y
L±R BR
R±B
Y±L
E
THROTTLE
POSITION
SENSOR AIR FLOW METER
ENGINE ECU (
M/T )
TO S UB THROTTL E
POSITION SENSOR
(
W/ TRACTI ON
CONTROL )
E11 , E1 2
AB
T2
A9
ENGINE AND ECT ECU (
A/T )
E9 ,E10
A
B
(
FOR USA SPEC. )
1 2 I34
I40I17
I23 I32 B17
E16 I13
I34
I32
IK1 1
BY16
BY1
5
IG33
IK 2
22 IK2 12 BY1 2
BY1
1
1
1 B
48 OX1
B
71 HT
B
61 OX3
EC
BT1
17
LG±B
W
BR
W
BR±W
BR±W W
BR±W
W
R±L
R±L R±L
B±R
BR
B±R
( SHIELDED )
(
SHIELDED )
(
SHIELDED )
W
BR±W
R±B
BR BR BR R±L
G B
L±Y
B±R
BR
BR
BR
BR
(SHIELDED )
G
B
L±Y
B±R BR BR B±R
BR
R±L
BR±W
BR
OXYGEN SENSOR SUB
(FOR USA SPEC. )
O8
42 13
(
*2 )
(
*1 )
(
*2 )(
*1 )
(
*3 )
O3
OXYGEN SENSOR
MAIN NO. 1
(
ON FRONT SIDE )
POWER STERRING
PRESSURE SW P20
O4
OXYGEN SENNSOR
MAIN NO. 2
( ON REAR SIDE )
(
SHIELDED )
(
*3 )
R±L
B±R
B±R
BR
BR (*2 )
( *1 )
BR
( SHIELDED )
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73
* 1 : W/ CD PLAYER
* 3 : FOR USA SPEC. *2:W/OCDPLAYER
8 13 715 2
3411912 8 3
E20 I32
I32
IJ 1 1 IK1
3
IK1
4
IK1
5IK1 2
EB1
2II1 5
B
4 E11
B
69 E1
B
28 VF2
B
29 VF1
A
20 TE1
A
3 KD
A
17 TT
A
23
ACMG A
34
A/C
IF
ED
BR
WGB
L±Y
B±R BR
B±R B±R
B±RLG
GR±Y
W
L±O
L±R W
GR±Y LG
GR±Y LG
B±Y BR
GR±Y LG
G±R
G±Y G±R
L
BR
L±Y B±R
B
G
W
BR
W
E1
+B
IG±
FP
OX
E1
OX2 TE1 VF1 ENG TE1 TT TE2 E11 , E1 2
T6
C3
FROM A/C MAGNETIC
CLUTCH RELAY
FROM A/C CONTROL
ASSEMBLY
ENGINE ECU (
M/T )
CHECK CONNE CTOR TDCL
(TOTAL DIAGNOSTIC
COMMUNICATION LINK )
A
B
IJ 1 12
R±L
I33
I32
BR
15 VF2
14
BR
BR
EC
E9 ,E10
ENGINE AND ECT ECU
(
A/T )
AB
IH1
2 IJ2
17
1 2IH1
1
A
19 TE 2
G±Y
W±B W±B L L
( SHIELDED )
(
SHIELDED )
B±R
BR B±R
(
SHIELDED )
KICK DOWN
SW
K3
BR
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74
ENGINE CONTROL
EFI MAIN RELAY2 ± 4: CLOSED WITH IGNITION SW AT ON OR ST POSITION
W 4 WATER TEMP. SENSOR
1 ± 2: APPROX. 16.2K (±20 °C, ±4°F)
: APPROX. 2.45K (20 °C, 68°F)
: APPROX. 0.32K (80 °C, 176 °F)
E 3 EGR GAS TEMP. SENSOR (FOR USA SPEC.)
1 ± 2: APPROX. 78.30K (50 °C, 122 °F)
APPROX. 13.06K (100 °C, 212 °F)
APPROX. 3.16K (150 °C, 302 °F)
E 9(A), E10(B) ENGINE AND ECT ECU, E11(A), E12(B) ENGINE ECU
(VOLTAGE AT ENGINE AND ECT ECU WIRING CONNECTORS)
BATT ± E1 : ALWAYS APPROX. 12 VOLTS
IGSW ± E1 : APPROX. 12 VOLTS WITH IGNITION SW ON
+B, +B1 ± E1 : APPROX. 12 VOLTS WITH IGNITION SW ON
VC ± E2 : 4±6 VOLTS WITH IGNITION SW ON
IDL1, IDL2 ± E2 : 0±1 VOLTS WITH IGNITION SW ON AND THROTTLE VALVE FULLY CLOSED
: 10±14 VOLTS WITH IGNITION SW ON AND THROTTLE VALVE FULLY OPEN
VTA1, VTA2 ± E2 : 0.1±1.0 VOLTS WITH IGNITION SW ON AND THROTTLE VALVE FULLY CLOSED
: 3±6 VOLTS WITH IGNITION SW ON AND THROTTLE VALVE FULLY OPEN
THA ± E2 : 1±3 VOLTS WITH IGNITION SW ON AND INTAKE AIR TEMP. 20°C ( 68°F)
THW ± E2 : 0.1±1.0 VOLTS WITH IGNITION SW ON AND COOLANT TEMP. 80°C ( 176 °F)
STA ± E1 : 6±14 VOLTS WITH ENGINE CRANKING
#10, #20, #30, #40, #50, #60 ± E1 : APPROX. 12 VOLTS WITH IGNITION SW ON
IGF ± E1 : 0±1 VOLTS WITH ENGINE IDLING
MREL ± E1 : APPROX. 12 VOLTS WITH IGNITION SW ON
DI ± E1 : 7.5±14 VOLTS WITH ENGINE IDLING
ISC1, ISC2, ISC3, ISC4 ± E1 : APPROX. 12 VOLTS WITH IGNITION SW ON
HTL1, HTR1, HTL2, HTR2 ± E01 : 0±2 VOLTS WITH ENGINE IDLING
EGR ± E1 : APPROX. 12 VOLTS WITH ENGINE IDLING
NSW ± E1 : 0±1 VOLTS WITH IGNITION SW ON AND SHIFT LEVER P OR N RANGE
: 10±14 VOLTS WITH IGNITION SW ON AND SHIFT EXCEPT P OR N RANGE
TE1 ± E1 : APPROX. 12 VOLTS WITH IGNITION SW ON
TE2 ± E2 : APPROX. 12 VOLTS WITH IGNITION SW ON
W ± E1 : APPROX. 12 VOLTS WITH ENGINE IDLING
0±2 VOLTS WITH IGNITION SW ON
A/C ± E1 : 0±2 VOLTS WITH AIR CONDITIONER ON
10±14 VOLTS WITH AIR CONDITIONER OFF
ACMG ± E1 : 0±2 VOLTS WITH AIR CONDITIONER ON
: 10±14 VOLTS WITH AIR CONDITIONER OFF
TR ± E1 : APPROX. 12 VOLTS WITH IGNITION SW ON
VTA1, VTA2 ± E2 : 0±1 VOLTS WITH IGNITION SW ON AND THROTTLE VALVE FULLY CLOSED
3±5.5 VOLTS WITH IGNITION SW ON AND THROTTLE VALVE FULLY OPEN
NE ± E1 : 4±6 VOLTS WITH IGNITION SW ON
(RESISTANCE OF ENGINE AND ECT ECU WIRING CONNECTORS)
+B, +B1 ± #10, #20, #30, #40, #50, #60 : 13.2±14.2
+B, +B1, ISC1, ISC2, ISC3, ISC4 : 10±30
+B, +B1 ±EGR: 33±39
+B, +B1, HT : 5.1±6.3
+B, +B1 ±EVAP : 30±34
IDL1, IDL2 E2 : INFINITY WITH THROTTLE VALVE OPEN 0±0.5WITH THROTTLE VALVE FULLY CLOSED
VTA1, VTA2 E2 : 2.4±10.7WITH THROTTLE VALVE FULLY OPEN
0.3±5.9 WITH THROTTLE VALVE FULLY CLOSED
VCC ± E2 : 3±7K
THW ± E2 : 200±400 WITH COOLANT TEMP. 80°C ( 176 °F)
THA ± E2 : 2±3K WITH INTAKE AIR TEMP. 20°C ( 68°F)
THG ± E2 : 69.4±88.5K WITH EGR GAS TEMP. 50°C ( 11 2 °F)
G1, G2 ±G± : 0.835±13.5K
NE± G± : 0.835±13.5K
SERVICE HINTS
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76
ENGINE CONTROL
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
A 926F1530K 329
C 326F1630N 127C13B28I 127O 327
C14A28I 227O 427C2328I 627O 831
D1326I 727P2027E 226I 827S 327
E 326I 927S1229E 9A28I1027T 227
E10B28I1127T 629E11A28I1529V 127
E12B28K 127V 227F 926K 227V 327
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
423LEFT 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
1E20INSTRUMENT PANEL WIRE1H1I20COWL WIRE1J20COWL WIRE
1K3A23INSTRUMENT PANEL WIRE3D23INSTRUMENT PANEL 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)
IG236INSTRUMENT PANEL WIRE AND COWL WIRE (R/B NO. 5)IG338INSTRUMENT PANEL WIRE AND COWL WIRE (RIGHT KICK PANEL)
IH136COWL NO. 2 WIRE AND COWL WIRE (BEHIND COMBINATION METER)II136ENGINE WIRE AND A/C WIRE (BEHIND GLOVE BOX)
IJ136ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)IJ236ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)
IK136ENGINE WIRE AND INSTRUMENT PANEL WIRE (RIGHT KICK PANEL)IK236ENGINE WIRE AND INSTRUMENT PANEL WIRE (RIGHT KICK PANEL)
BT140FLOOR WIRE AND COWL WIRE (LEFT KICK PANEL)BY140INSTRUMENT PANEL WIRE AND FLOOR NO.3 WIRE (RIGHT KICK PANEL)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
EB34FRONT SIDE OF LEFT FENDER
EC34FRONT SIDE OF INTAKE MANIFOLDED34REAR SIDE OF CYLINDER HEAD RH
IF36LEFT KICK PANELIH36UNDER THE ASHTRAY LH
BK40UNDER THE CENTER PILLAR LH
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77
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
E15I2238INSTRUMENT PANEL WIREE16I2338INSTRUMENT PANEL WIRE
E1734ENGINE WIREI32E1834ENGINE WIREI3338ENGINE WIREE20I3438ENGINE WIRE
I10I4038INSTRMENT PANEL WIREI1338COWL WIREB1240FLOOR MAIN WIREI1438COWL WIREB1740FLOOR NO.3 WIREI1738INSTRUMENT PANEL WIRE
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78
ENGINE CONTROL
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236
GROUND POINT
FRONT TURN SIGNAL
LIGHT LH
ENGINE HOOD
COURTESY SW
TRACTION PUMP AND
MOTOR
HEATER RELAY
ABS ACTUATOR RELAY
TELEPHONE
TRANSCEIVER
AND SPEAKER RELAY
ENGINE OIL LEVEL
WARNING SW
COMBINATION METER
(E1 )
EFI ECU
TRACTION ECU
CHECK CONNECTOR
(
E1 ) CORNERING LIGHT LH
FRONT SIDE MAKER
LIGHT LH
BRAKE FLUID LEVEL
SW
FRONT CLEARANCE
LIGHT LH
FRONT SIDE MAKER
LIGHT RH
FRONT CLEARANCE
LIGHT RH
ABS ACTUATOR
FRONT TURN SIGNAL
LIGHT RH
CRUISE CONTROL
ACTUATOR
OXYGEN SENSOR SUB
(
FOR USA SPEC. )
TDCL (
E1 )
WASHER LEVEL SW EFI MAIN RELAY
CORNERING LIGHT RH
A/C PRESSURE SW
(HI GH PRESSURE )
AIR FLOW METER POWER STERRI NG
PRESSURE SW
NOISE FI LTER
(
FOR IGNI TION SYSTEM ) E4
E10
E12 2
2
BS1 4 E4
E7
E1 E5
EB EA I23
I33
E1 6
I32
E20
E20
E20
IK2 24
ED EC IK1
1 BY1
5
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W± B W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B BR
BR
W±B BR
BR
BR
W±B BR
BR±B BR BR
BR
BR
W± B
W± B
W± B
W± B
W± B
W± B
W± B
W±B
W±B
BR
BR
BR
BR BR
BR
BR
W±B
BR BR
BR
( EO1 )
( E11 )
( E1 )
( EO2 )
I27BR
(
S1 )
( E1 )
NOISE FILTER (
FOR
IGNITION SYSTEM )W±B
W/ TRACTION SYSTEM
NOI SE FILTER
(
FOR DEFOGGER SYSTEM )
W±B
W±B
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240
GROUND POINT
: 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)
1D20FRONT DOOR LH WIRE
1E20INSTRUMENT PANEL WIRE
1F20ROOF WIRE
1G20COWL NO. 2 WIRE
1H
1J20COWL WIRE
1K
20COWL WIRE
3A
3D
3F22INSTRUMENT PANEL WIRE
3G
22INSTRUMENT PANEL WIRE
3H
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IE136ENGINE ROOM MAIN WIRE AND COWL WIRE (R/B NO.4)
IE236ENGINE ROOM MAIN WIRE AND COWL WIRE (BEHIND GLOVE BOX)
IF236FRONT DOOR LH WIRE AND COWL WIRE (LEFT KICK PANEL)
IG136INSTRUMENT PANEL WIRE AND COWL WIRE (R/B NO.5)
IH136COWL NO. 2 WIRE AND COWL WIRE (BEHIND COMBINATION METER)
IJ136ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)
IK136ENGINE WIRE AND INSTRUMENT PANEL WIRE (RIGHT KICK PANEL)IK236ENGINE WIRE AND INSTRUMENT PANEL WIRE (RIGHT KICK PANEL)
IN138ENGINE ROOM MAIN WIRE AND A/C WIRE (BEHIND GLOVE BOX)
IP138FRONT DOOR RH WIRE AND COWL WIRE (RIGHT KICK PANEL)
IQ138INSTRUMENT PANEL WIRE AND CONSOLE BOX WIRE (UNDER THE INSTRUMENT PANEL CENTER)IQ238INSTRUMENT PANEL WIRE AND CONSOLE BOX WIRE (UNDER THE INSTRUMENT PANEL CENTER)
BS140ENGINE ROOM MAIN WIRE AND FLOOR WIRE (LEFT KICK PANEL)
BT140FLOOR WIRE AND COWL WIRE (LEFT KICK PANEL)
BU140FLOOR WIRE AND INSTRUMENT PANEL WIRE (LEFT KICK PANEL)BU240FLOOR WIRE AND INSTRUMENT PANEL WIRE (LEFT KICK PANEL)
BV240FLOOR NO. 3 WIRE AND CONSOLE BOX WIRE (UNDER THE INSTRUMENT PANEL CENTER)
BX140FLOOR NO. 3 WIRE AND COWL WIRE (RIGHT KICK PANEL)
BY140INSTRUMENT PANEL WIRE AND FLOOR NO. 3 WIRE (RIGHT KICK PANEL)
BZ140ROOF WIRE AND MOON ROOF WIRE (FRONT SIDE OF ROOF LEFT)
Ba142FLOOR WIRE AND FRONT SEAT LH WIRE (UNDER THE FRONT LH SEAT)Ba242FLOOR WIRE AND FRONT SEAT LH WIRE (UNDER THE FRONT LH SEAT)
Bb142FLOOR NO. 3 WIRE AND FRONT SEAT RH WIRE (UNDER THE FRONT RH SEAT)
Bd142FLOOR NO. 3 WIRE AND LUGGAGE NO. 2 WIRE (RIGHT SIDE OF LUGGAGE COMPARTMENT)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
EA34FRONT SIDE OF RIGHT FENDER
EB34FRONT SIDE OF LEFT FENDER
EC34REAR SIDE OF INTAKE MANIFOLD
ED34REAR SIDE OF CYLINDER HEAD RH
IF36LEFT KICK PANEL
IG36INSTRUMENT PANEL BRACE LH
IH36UNDER THE ASHTRAY LH
II36UNDER THE ASHTRAY RH
IJ36RIGHT KICK PANEL
BK40UNDER THE CENTER PILLAR LH
BL40UNDER THE CENTER PILLAR RH
BM40BACK PANEL CENTER
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