water LEXUS SC300 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
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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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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567 8
EB1
EC ED D DCCCCD
CCCC
C IJ2 IJ2
IG2
EB1
C D C DC C CCC
DDCDDDDDCCCCC
ED
1 2
1
2 23
1 23
14
4 234 51
25
1346
2
B±O
B±W B±OB±Y
B± R
B± R
W
R± LBR
B± R B±Y W
L±R
B±Y LG
GR±Y B Y B
G±W L±Y
R± G P B± R
B± R
18 19 17 16 15 46 23 44 34
31 32 34 32 35 33 33 24 2 76 1 37B
B± Y
B±R W
L±R
W± B
W± B
BR
LG±BL±WV±R
G± YB± Y
B± O P
B±W B± O
BR
W
L±R
B±R
P
B±O
BR
BR
#30 #20 #40 #50 #60 THG ACMG THW A/C
B±R
B±R
B±R
EB1
Fro m
Spe ed Sen sor
< 21±7>
P± L
Y± L
V± Y
Y± G
W± Y Y±R
L±R
Y± B
Y± G L±R
L±R
BR
BR
65 63 42 64 43 38 39 40 58 57 41 45 66 A9
AIR FLOW METER
From Trac tion ECU
< 8±8>
From I gniter
< 1±6>
7P
E2 IDL2 VTA2
IDL1
VTA1
THA
VC KS
IGT
IGF
VT 01
VT 02
NEO
TR
IGSW
NS W
SP1
M±REL
BATT
ISC3
ISC1
ISC4
ISC2
+B1
+B I1
ISC
VALVEBR
R±BBR
Y± L
L±R
R
Y
L±R
L±R
L±R
BR
L±R
BR
BR
BR
BR
BR W
G
From Magnet ic
Cl ut ch Rel ay
< 22±1>
To A/ C Amp lif ie r
< 22±7>
E3
EGR GAS TEMP. SENSOR
E2
EFI WATER TEMP. SENSOR
S9
SUB THROTTL E
POSITI ON SENSOR T2
THROTTLE
POSITI ON SENSOR
BR
Engine Control
2LEXUSSC300
(
Cont ' d )
ENGI NE AND ECT ECU, ENGI NE ECU *
1: (
w/ Trac tion Control )
(
* 1)
( * 2)
( * 1)
( * 2)
(
* 1 ) *
2:
(
w/ o Tr a ct i o n Co nt r ol )
(
* 1 ) To Trac ti on
ECU< 8±8>
R±B
R
4311 8
B±O
BR (
* 3)
(
* 3) *
3: (
US A S pe c. )
* 4:
(
Ex . USA Spe c. )
E9 , E10 DC
BR
Front side of
intake manifold Rear side of
c ylinder head RH Rear side of
c ylinder head RH
C
C
C 1 2
1
2
2
1
C
C
C
C
C
C
D
D
C
C
C
C
D
D
C
D
C
D
D
20
77
27
7
25
26
22
21
80
79
4
69
4
6
29
20
28
19
17
V7
VSV (
for Int ake
Contr ol Valve )
V2
VSV
(
for EVAP )
V1
VSV
(
for EGR )
BY1
BY1
BY1 BY1
BR
R±B
(
* 4 )
W
(
* 4 )
B±R
BR±W
(
* 3 )
R±L
(
* 3
)
3142 1256
IK2
IK2
12
22
C
C
1
O3
OXYGEN SENSOR
MAIN No. 1
(
ON Front Side )
C48 71 61 75 74
1
O4
OXYGEN SENSOR
MAIN No. 2
(
ON Rear Side )
C
D
1 2
35 47
P2 0
POWER STEERING
PRESSURE SW
IK11
IJ1
IJ1
(SHIELDED )2341 C
C
1
1 49
50
D1 3
DI ST RI B UTOR
( SHIELDED )
EC
Front side of
intake manifold
G±Y G± R
8
14
K1
No. 1(
ON Fr ont Side )
KNOCK SENSOR
K2
No. 2 (
ON Rear Side ) BR BR
BR
W
W L
B Y
R R±G
P
W± B
W± B G±W
L±Y
GR±Y LG
B±Y
G±Y
BR
BR
BR
G1 G2 G± NE
#10
TT TE2 VF2 TE1 VF1 W STP E1 E1 1 E0 2 E01 DI FPC G1 G2 G± NE KNK1 KNK2 STA ACI S
PS OX2 OX1 HT OX3 EGR EVAP 39
G± R G±B
B±W BR± W
BR± W
BR
B±R
B±R
B±R
B±R
W
BR± W
W
R±L
BR BR
BR
R±L W
LG±B BR
BR
(
SHI ELDED )
(
SHI EL DED )
(
SHI ELDED )
( SHIELDED )
O8
OXYGEN SENSOR SUB
(
for California )
BR
BR
Y B
R± L
BR
(* 4)
(
* 4)
(A/ T )
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567 8
21 LEXUS SC300(
Cont ' d )
AIR BAG
CHA RGE
OIL
OIL LEVEL COOLANT
LEVEL REAR
LI GHT
PWR
ABS TRAC
TRAC OFF
CRUISE WASHER
O/ D OFF
FUEL
SEAT BELTP
R N D 2 L
A
C
C A
A
B
B
B
C
C
C
C
C
C
C
B C
C
B
B
BA
B
A
A
C
CA A A A A A A A
C
C
C
C C C A C C B B B B
B A A C C
10 : 00
BK 1E
18 3D
10
3A
1
1J
1 1K
12
IH IF ED
IK1
8
IK2 IK1
9
1
E
3
E
2
E
1
D
BU110
BU1
3
BU1
4 11
11
1
14
19
8
18
11
13 6
18
17
16
20
19
15
13
3
15 5
1
20 9
18 8
11
87 1 2 3 4 5 16 17
2
3
4
5 10 9
12 23 12 4 17 16 7
6
15
10 22 21
W± R
RY
B±O
Y±B
V± R
V±Y
R±W
L±R
W
R± Y B
V±W V
R
L±R
P±L
Y±B
B±Y
B± W
W±B BR
B
W± B W± B BR±B
Y± G
B
Y±G
BR±B
W± B
W±B
W±B
BR±B W± B BR
Y±G
WATER
TEMP.HI GH BEAM TURN
LH
RH
BRAKE DOOR
TACHO
TRI P
SPEED
ILLUMINATIONCHECK±
ENGINE
FUEL
See Taillight and
St op Light Sy stem
<4±6><5±6>
SeeEngineControlSystem
<2±3>
Se e ABS Sy st e m< 8± 7> < 9± 3>
See Cruise Control System
< 16±3>Se e ABS an d Tr act io n
Control System< 8±7>
SeeECTandA/TIndicator
System< 3±5>
D
F1 7 , F18 E
FUEL SENDER Y±B
B±Y
B±W 24
See SRS Airbag System< 15±4>
See Charging Sy stem< 1±2>
See Headlight Sys tem< 4±1> < 5±1>
See Turn Signal and
Hazard Warning
Light Sy stem< 7±3>
See ECT System< 3±5>
From Neutr al St art SW< 1±3>
See Interier Light System< 6±3> From Igniter º TACº < 1±5>
To Engine and ECT ECU< 2±7>
To Cruise Control ECU< 16±3>
To PPS ECU< 15±2> See Illumination System
<4±7><5±7>
See ECT and A/T Indic ator
Syst em< 3±6>
See Unlock and Seat Belt
Warning Syst em< 4±4> < 5±4>
W3
WATER TEMP.
SENDER
Combination Meter
1
COMBINATION METER C12 , C13 , C14
A
AB IG1
8
Under the
c ent er
pillar LH Under the
as htr ay LH
Lef t
kick panelRear side of
c ylinder head RH
C
2
G 2
F
1
F 14
L±R
P
P
SH OR T C ON NE CT OR
S2 2 G , S23 F L±R
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567 8
22 LEXUS SC300(
Cont ' d )
12
II1
7
II1 2 IR2
5
IR2 4
IR2
IR1
IR1
IR1
IR1
IR2
IR2
IR2
IR2 1J
82
1E
22
5
1B
3A 3A
3A
3E
3H 3G 3B
3G
11
1E
IQ1
IQ1 IQ1 IQ1 IQ1 IQ1 II1
5
IR2
IR1
IR1
IR1
IN1
4
EB1
12 IR1
13
IR1
IR1 5
IQ117
IQ1 6
IQ1 21 12 31
IQ1 16
D
D
D
D
D
D
C
D D
D
E
E
D
IR1
4
D
C
C
D
D
E
IQ1
D
E C
D
C
E
E
E
D
D D D
D D
IQ1
C E
D
IR1
IR2
5IN11E
18
1J
1
EA IF
POWER
VOLUME AUTO
BCD SW
(Room Temp.
Contr ol SW )
M
EIR1
M
W
P± L
R±L
L±W
G± Y
G± R[ R±L
R± W
BR±W G±W BR
R±Y V
W±G BR
G± Y
Y
B±R R± G
B±Y
B±R Y
G±O V±R
V±W
L±W
BR±W G±W BR
R±Y V
L±Y
G± Y Y
B±R P± L
P
GR
G±R G Y±L
Y±G L±Y
LG±R
Y± R
L
W
L±B
Y± B P±B
W± B R
L±R
R± Y B
L±R L±O
B
R± Y L±R R
W± B P±B
L±B Y±L W
L
Y±G
LG±R
L±Y
Y±R Y± L BR
BR
BR
BR
BR
BR±W
BR
BR±W
BR±W BRBR±W
Y± GBRW
Y± L
P± B
W± B
R
BR±W
G±W BR
R±Y V
W±G BR
G± Y
Y
B±R P± L
P±B
P± B
BR
GR
BR
LG
R±L
R±L
B± Y B±Y
R± L B±Y
P± L
W
L±R
L±W
BR±W BR
BR±W
BR±W
GRBR
G±R
BR L±G
L±G
W±B
W±B W±B R
L±R
BR± W
BR
L±W
BR
BR± W
11
12
13
14
351 2 2
4
5
6
7
8
9
3
4
4
2
1
6
1
1
W/ V
MGCIGN
RDFGR ACC+B
E
DI N
MDEF
LP
MFACE TC
TPM
TW
TE
ST
TR
IG+
SET5
SET4
SET3
SET2
SET1
SAUTO
HR
S5
TP
SG
MC
MH
A/ CI N
LCKIN
LV
BL R
DOUT
TAM
TPI
MR EC
MF RS
4 5
23
8
17
8 7 3 2
16
15
14
13
12
4
9
18
22
20 3
2
7 11 9
10 25 5 8
8
1
2
3
3
2
1 9 9
5
18
8 6
10 6
8 10 1 9 13
5 9 6 7 1 15 10 15
1 4 3
127
11
7
Automatic Air Conditioner
3 1 6 5
13 3 3 5
5
12
6 19 IR2
10
DEF FACE
A3
A/C PRESSURE SW
V4
VSV(
for Water Valve )
A15
A/C CONTROL
SW AND
RADIO SW
To TDCL< 2 ±4 >
A1
A/C AMBIENT
TEMP. SENSOR
A3 3
AI R INLET CONTROL
SERVO MOTOR
To Engine and ECT ECU
<2±7>
From I gniter
< 1±5>
From Defogger
Relay< 15±3>
To TDCL< 2±4>
From Rheostat < 5±7> < 6±7> A28
AIR VENT MODE
CONTROL SERVO
MOTOR
W6
WATER TEMP. SENSOR
(
for A/C System )
A16
A/C EVAPORATOR
TEMP. SENSOR
A20
A/C SOLAR SENSOR
A19
A/C ROOM TEMP. SENSOR 15A
CIG
10A
DOME
A12 , A13 , A14
ECD
A/ C CONTROL ASSEMBLY
II1 II1
1
4
BR
G±Y
7
BR
RECIRC FRESH
3H
12 IK110
To Check Connec tor
< 2±3>BR BR
P±B P±B
Fr ont side
of right
fender Lef t kic k panel
1
2
R±LN4
NOI SE FILTER C
3
E
6
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52
POWER SOURCE (Current Flow Chart)*1: USA
*2: CANADA
T9 T19T11 T12
T10 W5
V3 V5 V6 W3 W2
188
11 2
194
204 200
162 216
V4 200
112 90 134 68 156
192
226 94
VSV (for EVAP) Tension Reducer
Solenoid LHTheft
Deterrent and
Door Lock ECU
Tilt and power
Telescopic ECU
Seat Heater SW (A/T)
Traction Cut SWTrip SW and
Theft Deterrent Indicator
Telephone Transceiver and
Speaker Relay
Tension Reducer
Solenoid RHVSV
(for EGR)(EX. California)
Washer Level SW Vanity Light LH
Vanity Light RH
Washer Motor
Water Temp Sender
Wiper MotorVSV (
for Water Valve)
VSV (
for Fuel Pressure Up)
*Page Nos. of
Related Systems
Parts
Code or
Location
CB or Fuse
50A DEFOG
30A DOOR
30A POWER
15A STOP
15A ECU±B
10A MIR±HTR
10A HEATER
20A TURN
20A WIPER
10A GAUGE
15A ECU±IG
7.5A ENGINE
7.5A IGN
15A CIG
7.5A RADIO No.2
15A TAIL
7.5A PANEL
7.5A ST
15A TEL
10A DOME
20A RADIO No.1
25A HAZ±HORN
30A EFI
7.5A ALT SENCING
15A HEAD LH*1
15A HEAD RH*1
15A HEAD LH±LWR*2
15A HEAD RH±LWR*2
15A HEAD LH±UPR
15A HEAD RH±UPR
60A HEATER
7.5A TRAC
15A SEAT±HTR
Location
216
90
216
Traction ECU
Traction ECU
W1
V1 V2
T18
T16
T15
T14
T13
T8


* These are the page numbers of the first page on which the related system\
is shown.
The part indicated is located somewhere in the system, not necessarily o\
n the page indicated here.
[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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12
TROUBLESHOOTING
HOW TO REPLACE TERMINAL
(with terminal retainer or secondary locking
device)
1. PREPARE THE SPECIAL TOOLHINT: To remove the terminal from the connector, please construct and use the special tool or like object shown
on the left.
2. DISCONNECT CONNECTOR
3. DISENGAGE THE SECONDARY LOCKING DEVICE OR TERMINAL RETAINER
(a) Locking device must be disengaged before theterminal locking clip can be released and the terminal
removed from the connector.
(b) Use a special tool or the terminal pick to unlock the secondary locking device or terminal retainer.
NOTICE:
Do not remove the terminal retainer from connector
body.
For Non±Waterproof Type Connector
HINT: The needle insertion position varies according to the connector's shape (number of terminals
etc.), so check the position before inserting it.
ªCase 1º Raise the terminal retainer up to the temporary
lock position.
ªCase 2º Open the secondary locking device.
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13
For Waterproof Type Connector
HINT: Terminal retainer color is differentaccording to connector body.
Example:
Terminal Retainer
: Connector Body
Black or White : Gray
Black or White : Dark Gray
Gray or White : Black
ªCase 1º Type where terminal retainer is pulled up
to the temporary lock position (Pull Type).
Insert the special tool into the terminal
retainer access hole ( Mark) and pull the
terminal retainer up to the temporary lock
position.
HINT: The needle insertion position varies according to the connector's shape
(Number of terminals, etc.), so check the
position before inserting it.
ªCase 2º Type which cannot be pulled as far as
Power Lock
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