ECU LEXUS SC400 1991 Service Repair Manual

LEXUS SC400 1991 Service Repair Manual SC400 1991 LEXUS LEXUS https://www.carmanualsonline.info/img/36/57051/w960_57051-0.png LEXUS SC400 1991 Service Repair Manual

Page 3894 of 4087

LEXUS SC400 1991  Service Repair Manual 
127
2 1
2
1
E18 E20
E20 I32
I32
B
27 B
4B 28 A20 B 29
B
42 B 63 B 41 B43 B64 B65 B 44 B 23 B3
ED
E18
L±R
Y±L
R±B
BR
L±R Y
R BR
BR
Y±L
R±B
L±R Y
R
BR
G
P
V
GR±Y LG
B±Y BR
LG
BR
W±B
BR L
LG
G

Page 3895 of 4087

LEXUS SC400 1991  Service Repair Manual 
128
ECT AND A/T INDICATOR
POWER NORMAL
3 4
71529 1 2 IJ 2
3
IK1
5IK1 2IK1 22
IJ 1
6
IK1
21
IG2
7
1E
12
1K
4
3D
3
3D
63B 43B
53D
3A
4
3D13 1H
12
B
76
NSW A
18
P A
9
2 A
10
L A
2
SP1
B
17 TT
A
19 TE2
A

Page 3897 of 4087

LEXUS SC400 1991  Service Repair Manual 
130
ECT AND A/T INDICATOR
THIS SYSTEM, ELECTRICALLY CONTROLS THE LINE PRESSURE, THROTTLE PRESSURE, LOCK±UP PRESSURE AND\
 ACCUMULATOR
PRESSURE ETC. THROUGH THE SOLENOID VALVE. THE ECT IS A SYSTEM WH

Page 3898 of 4087

LEXUS SC400 1991  Service Repair Manual 
131
E 1  ECT SOLENOID
1±4 :  APPROX.  5.3
2±5 :  APPROX.  3.7
3±GROUND : APPROX.  13.2
6±GROUND : APPROX.  13.2
E 2  EFI WATER TEMP. SENSOR
1±2 : APPROX.  16.2K  ( ±20 °C  ±4 °F)
APPROX

Page 3901 of 4087

LEXUS SC400 1991  Service Repair Manual 
66
.
ENGINE CONTROL
THIS SYSTEM UTILIZES AN ECU AND MAINTAINS OVERALL CONTROL OF THE ENGINE, TRANSMISSION AND SO ON. AN OUTLINE O\
F
THE ENGINE CONTROL IS EXPLAINED HERE.
1. INPUT SIGNALS
(1) WATER T

Page 3902 of 4087

LEXUS SC400 1991  Service Repair Manual 
67
2. CONTROL SYSTEM
*EFI (ELECTRONIC FUEL INJECTION) SYSTEM
THE EFI SYSTEM MONITORS THE ENGINE CONDITION THROUGH THE SIGNALS INPUT FROM EACH SENSOR (IN\
PUT SIGNALS
FROM (1) TO (13) ETC.) TO THE ECU

Page 3904 of 4087

LEXUS SC400 1991  Service Repair Manual 
69
E2022 22
1H
12
2
22
22 1I
10
P
N
3
2
1 2
EB2
1
IE1
15 IJ2
7 IJ1
10 IK1 7
IK1
6
1J
3
1E12
31 23 132
1
4
52 I32
EB1
3 EB2 1
VCC OUT GNDY
L±R
B±O B
Y
B
L±R
W
B±O
B±R B±Y
B±W
B±R B±O
B±W B±

Page 3905 of 4087

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
E

Page 3906 of 4087

LEXUS SC400 1991  Service Repair Manual 
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

Page 3907 of 4087

LEXUS SC400 1991  Service Repair Manual 
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