sensor LEXUS SC400 1991 Service Repair Manual
Page 3918 of 4087
17
1. NORMALLYOPENOpens and
closes circuits,
thereby
stopping (1) or
allowing (2)
current flow.
RESISTOR An electrical component with a
fixed resistance, placed in a circuit
to reduce voltage to a specific
value.
RESISTOR, TAPPED A resistor which supplies two or
more different non±adjustable
resistance values.
SENSOR (Thermistor) A resistor which varies its
resistance with temperature.
SHORT PIN Used to provide an unbroken
connection within a junction block.
SOLENOID An electromagnetic coil which
forms a magnetic field when
current flows, to move a plunger,
etc. SWITCH, DOUBLE THROW
A switch which continuously
passes current through one set
of contacts or the other.
SWITCH,
IGNITION A key operated switch with
several positions which allows
various circuits, particularly the
primary ignition circuit, to
become operational.
Wires are always
drawn as straight lines
on wiring diagrams.
Crossed wires (1)
without a black dot at
the junction are not
joined; crossed wires
(2) with a black dot or
octagonal (
) mark at
the junction are spliced
(joined) connections.
RELAY, DOUBLE THROW
A relay which passes current
through one set of contacts or the
other.
SENSOR, ANALOG SPEED Uses magnetic impulses to open
and close a switch to create a
signal for activation of other
components. TRANSISTOR
A solidstate device typically used
as an electronic relay; stops or
passes current depending on the
voltage applied at ªbase.º
SWITCH, WIPER PARK
Automatically returns wipers to
the stop position when the wiper
switch is turned off.
SWITCH, MANUAL SPEAKER
An electromechanical device
which creates sound waves from
current flow.
2. NORMALLY CLOSED
RESISTOR, VARIABLE OR
RHEOSTAT A controllable resistor with a
variable rate of resistance.
Also called a potentiometer or
rheostat.
2. NORMALLY
OPEN
RELAY
1. NORMALLY
CLOSED Basically, an electrically
operated switch which may
be normally closed (1) or
open (2).
Current flow through a
small coil creates a
magnetic field which either
opens or closes an
attached switch.
(2) SPLICEDWIRES
(1) NOT CONNECTED
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Page 3919 of 4087
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
WhereEverybodyKnowsYourName
Page 3920 of 4087
237
GLOVE BOX LIGHT SW
CIGARETTE LIGHTER
LUGGAGE COMPARTMENT
DOOR OPENER SW
COMBINATION METER
(EP )
O/D MAIN SW
RHEOSTAT
DO OR LOCK MOTOR,
DOOR UNLOCK
DETECTION SW AND
DOOR OPEN DETECTION
SW LH
MIRROR HEATER LH DOOR KEY LOCK AND
UNLOCK SW LH
POWER WINDOW
MASTER SW
RE MOTE CO NTROL
MIRROR SW
KEY INTER LOCK
SOLENOID
[IGNITION SW]
UNLOCK WA RNING SW
[IGNITION SW]
TURN SIGNAL SW
[COMB. SW]
WIPER AND WASHER SW
[COMB. SW]
LIGHT CONTROL SW
[COMB. SW]
DIMMER SW
[COMB. SW] INTEGRATION RELAY POWER MAIN RELAY HA ZARD S W A/C CONTROL
ASSEMBLY A/T INDICATOR LIGHT
(
FOR SHIFT LEVER )
SEAT HEATER SW TRACTION CUT SW AND
SEAT HEATER SW SHIFT LOCK ECU
3G 8
3F 8
3F 7
3D 10
3D 9
3A 2
1F 6
1K 6 3H
15
3H 14
3H 3
1D 10
1G 3
1G 4
IF
IG 1E
18 3A
1
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
CE NTER AI RB AG
SENSOR ASSEMBLY
I29
W±B
W±B
3G
3
I38 I8 1K 5
WIPER MOTOR
SEAT HEATER RELAY
KICK DOWN SW
THEFT DETERRENT
AND DOOR LOCK ECU
HE ADLIGHT HI RH
HE ADLIGHT HI LH
COMBINATION METER
(
HIGH BEAM )
CRUISE CONTROL SW
[COMB. SW] E3
I1
4
4
1K
12
IE1
11
IH11
CRUISE CONTROL ECU
( GND ) 1J
1
I7
1G1
8
I5 W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B R
W±B
W±B W±B W±B W±B W±BW±BW±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
IQ1 10
W±B
(E1 )
( E2 )
TILT AND POWER
TELESCOPIC ECU
( GND2 )
W±B ( A/T )
( M/T )
W±B
1H 13
I38
B4
B31
MOO N ROOF CO NTROL
RE LAY
MOON ROOF LIMIT SW
MOO N ROOF MOTOR
MOO N ROOF CO NTROL
SW
PERSONAL LIGHT
VANITY LIGHT LH
VANITY LIGHT RH
PERSONAL LIGHT
VANITY LIGHT RH
VANITY LIGHT LH B3
B1
B1
B2
B
W±B B
W±B
W±B
W±B
W±B
W±B
W±B
W±B W±BW±B
BZ1
4 BZ1
5
B
W±B
W±B
( CANADA )
W±B
( W/O MOON ROOF )(
W/ MOON ROOF )
(
W/O MEMORY MIRROR )
W±B
(
CANADA )
WhereEverybodyKnowsYourName
Page 3922 of 4087
239
*2 : W/O DRIVING POSITION MEMORY
* 1 : W/ DRIVING POSITION MEMORY
TILT AND POWER
TELESCOPIC
ECU
(
ECUE )
RECLINING POS ITIO N
SENSOR
[POWER SEAT MOTOR]
SLIDE P OSITION
SENSOR LH
POWER SEAT
CONTROL SW
( FOR DRIVER' S SEAT )
FRONT VARTICAL
POSITION SENSOR
REAR VARTICAL
POSITION SENSOR
POWER SEAT ECU
( FOR DRIVER' S SEAT )
COMBINATION
METER (
E2 ) I5
B28
B26 B27 B 8 Ba213 BT1
13
IF2 13
BU1
6
IH
POWER SEAT ECU
( FOR DRIVER' S SEAT )
POWER SEAT
CONTROL SW
( FOR DRIVER' S SEAT )
SEAT HEATER LH
( FOR DRIVER' S
SEAT BACK )
BUCKLE SW LH
FUEL SENDER
FUEL P UM P
FUEL PUMP ECU AUTO ANTENNA
MOTOR
LIGHT FAILURE
SENSOR LUGGAGE COMPARTMENT
KEYUNLOCKSW
LICENCE PLATE LIGHT
REAR COMB. LIG HT
LH
RE AR COMB. LIGHT
RH
B26 B27
B13 I 22 B14
B15
BK BM
Ba1
12
Ba2
5
BR±B
BR±B
BR±B
BR±B
BR±B
BR±B
BR±B
BR±B
BR BR±B
BR±B
BR±B BR±B BR±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±B
BR±B
BR±B
BR
W±B W±B
(
GND )
( GND2 )(
W/ MEMORY )
( W/ MEMORY )
W±B
DRIVING POSITION
MEMORY AND RETURN SW
(*1)
( * 2)
WhereEverybodyKnowsYourName
Page 3956 of 4087
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 )
WhereEverybodyKnowsYourName
Page 3957 of 4087
OVERALL ELECTRICAL WIRING DIAGRAM
1234
3 LEXUS SC300 (
Cont . ne xt pa ge )
4 ACC
IG1
ST1
IG2
AM1 2
6
11 AM2
1J
7 21J
3
2
2
1B
4
2221I
5
EB1 EB2 4 EB1 11 IJ2 3 IJ2
16 IE1
9BS2
B
S1
B
OD1
8BS3
80 BEO1
79 BEO2
42 BVTA2
63 BIDL2
23 BSP2
3BSP2±
69 BE1
4BE11
24 A
M±REL 32 A
+B 1 31 A
+B 33 A
BATT 76 B
NSW
1A
IGSW 2A
SP1 41 B
VC 43 B
VT A1 65 B
E2 64 B
IDL1 44 B
THW 26 B
G1 25 B
G2 6B
G± 5B
NE 10 A
L 9A
2
4 3
4 2
123 SeeEngineControl
Sy stem< 2±8>
See Engine Contr ol
Syst em< 2±6>
W±R W± R B±Y
W± L
W
B±OW
B±O
B± O
B±R
B±R
B±R
B±O
B±Y
B±O PP B±OB±Y
BR±Y
W± RR± L
EB EE EE 1218 A
P 28 A
OD2 12 A
OD1
17 A TT
29 B VF1
20 A TE1
28 B VF 2
21 IK1 22 IK1
3 4
See Engine Contr ol Sy stem< 2±5>
W
G
G± O Y
GR ±R
W±B
W±B
W±B
BR
BR W± B
W± B
P
V BR
BR
WG
G±O
GR±R BR± Y W± B
G±O G±O Y G± O
W
B±Y
I15
IGNITION SW
W± R W W
60A MAIN
100A AM1
120A ALT
30A AM2
30A INJ
F9
FUSE BLOCK
40A IGSW
EF I
MAIN
RE LA Y
30A
EFI
7. 5A
IGN
3 1
83B±RE1
ECT SOLENOID
NO. 1 NO. 2
NO. 3
S4
SPEED SENSOR
NO. 2 (
for ECT ) E8
ECT
PATTERN
SELECT SW
From Combination
Meter< 21±4>
To Cruise Cont rol ECU
< 16±3>
See Engine Contr ol Sy stem
< 2±7>
B± Y
ENGI NE AND ECT ECU
Power
Source ECT and A/T Indicator
BATTERY
7 4 91413
6
POWER
NORMAL
A
19 TE2
E9 , E10
BA ENGI NE AND ECT ECU
ENGINE AND ECT ECU
Fr ont s ide of
left fender Rear side of
c ylinder head LH Rear s ide of
cy linder head LH
3
1
To Cruise Control
ECU< 16±3>
See Engine Control
Sy st e m< 2 ±8 > LG
Y B
W12 10 10
30
50
70
1
21
41
61 2
22
42
62 3
23
43
63 4
24
44
64 5
25
45
65 6
26
46
66 7
27
47
67 8
28
48
68 9
29
49
69 11
31
51
71 20
40
60
80
19
39
59
79
18
38
58
78
17
37
57
77
16
36
56
76
15
35
55
75
14
34
54
74
13
33
53
73
12
32
52
72
1020
30
40
1
11
21
31 2
12
22
32 3
13
23
33 4
14
24
34 5
15
25
35 6
16
26
36 7
17
27
37 8
18
28
38 9
19
29
39
A
E1 0 DARK GRAY
B
E 9 DARK GRAY
WhereEverybodyKnowsYourName
Page 3960 of 4087
567 8
4LEXUSSC300(
Cont ' d )
1
2
1
2 1D
11 E 1I
10
3G
1
1B
2
3A
9
1C
10
1E
20
1H
1
9BU1
1Bd15IG7
11 Bc 1
Be1 2 1
1
2
3A
10
1 2
3 84
921117
3G
83A 2
3A
1
2
12
1
1
4
1
2 1
2
EA BM BL 2Bd14
1
3
8
2 10
3H
3
3C
3
3F
2
3G
5
3H
1
3F 6
1
2
1
3
2
2
9
5
1
10
F 5
G
IQ1
2
6
7 IQ1
4
12
3A 9
3E 6
3E 6
3E
6
3H 2
3H 1
3H 1
2
10 11 1 2
GW±G
G
G
GW±G W± GW±G
GW±G
G±O
G±O
G±O
G±O
G±O W±G W± G W± G
W± G W± G
W± G
G± W
W± BY Y
G±O
G
G
W± L
G
G
G
GW±BW± B W± B W± B
G
Y
V± G
V± G Y
G±W
G± W
W±B
GGGG
G
W
G± W
G± W
B
W± B R± W
B
G±W G±W G±O
G±O
W± B W
W±GBR
Y± V L±B L
W±B
W± B
W± B
W±B
W±B
G
G
W± G W± G
W±B
±PK ±STP E HS +STP
ETCRLRVREILL±
7
G± O
G± O
+PK BWRN
T
15A
STOP
F3
LH
F4
RH
FRONT
CLEARANCE LI GHT
L3
LI GHT FAILURE SENSOR
RE AR LI GHT WARNI NG
LI GHT[ COMB. MET ER]
S12
STOP LIGHT SW
To ABS ECU<8±3><9±4>
To Shif t Lock ECU< 15±2>
G2
GLOVE BOX
LI GHT SW
F5
LH
F6
RH
FRONT SIDE
MARKER LIGHT
L2
LI CE NCE
PLATE LIGHT
W± B W±B
W±BH9
HIGH MOUNT
STOP LIGHT
H8
HIGH MOUNT
STOP LIGHT A1
A/C CONTROL
ASSEMBLY
A15
A / C C ON TR OL SW
AND RADIO SW
RADIO AND PLAYER
( w/o CD Player )
R4
RADIO AND PLAYER
( w/ CD Player )
T1 2
TRACTION CUT SW AND
SEAT HEATER SW
C1 1
CIGARETTE LIGHTER
A21
A/T INDICATOR LIGHT E8
ECT PATTERN
SELECT SW
T1 5
TRIP SW AND THEFT DETERRENT
INDICATOR LI GHT
R9
RHEOSTAT
G1
GLOVE BOX
55
13 13W±B
W±B
W± B W± B W± B
R± W
G±R
R± W G±R G±RTAI L AND
STOP LIGHT
[REAR COMB.
LIGHT]
R1 0
LH
R1 1
RH
TAIL
ST OP
TAIL
ST OP
To Engine and ECT ECU< 2±3>
To Traction ECU< 8±8>
To Cr uise Control ECU< 16±4>
To Cruise c ont rol
ECU< 16±4>
To Po wer Se at E CU
(Driver' s )
< 11±5>
G± W
G±W
(
* 1 )
(
* 2 )
( * 2 )
(
* 1
)
C13 , C14
ED
H
H
H
H
I3C
1
17
2345
COMBINATI ON METER C12 , C14 IH R5 , R6
FG
12 34
5678910
12
3456
RADIO AND PLAYER
(
w/ o CD Pl ay er )
Taillight and Stop Light (
for USA )
Illumination(
for USA )
*2:
(
w/o Rear Spoiler )
*
1: (
w/ Rear Spoiler )
W
G±W
G± O
Fro nt s i de of
right fender Under t he
c ent er pillar RH
Back panel c ent er 23
G
W± G
H7
HA ZA RD SW
10 11 12 13 17 18 19 20 21
12345 6789
14 15 16
17 18
1 2345 6789 10
23
22
21
20
19
15
14
13
12
11 16 C1 2 I
C1 4 H
COMBI NATI ON METER
RE AR LI GHT WARNI NG
LI GHT[ COMB. MET ER]
WhereEverybodyKnowsYourName
Page 3962 of 4087
567 8
5LEXUSSC300(
Cont ' d )
1
2
1
2 1D
11 E 1I
10
3G
1
1B
2
3A
9
1C
10
1E
20
1H
1
9BU1
1Bd15IG7
11 Bc 1
Bc1 2 1
1 2
3A
10
1 2
3 84
921117
3G
83A 2
3A
1
2
12
1
1
4
1
2 1
2
EA BM BL 2Bd14
1
3
8
2 3
3C
3
3F
5
3H
1
3F 1
2
1
3
2
9
5
1
10
F 5
G
6
7
12
3A 9
3E 6
3E 6
3E
6
3H 2
3H 1
3H 1
2
10 11 1 2
G
GW±G
W± G
GW±G
G±O
G±O
G±O
G±O
G±O W± G W± G W± G
W± G W± G
W± G
G± W
W± BY Y
G±O
G
G
W± L
G
G
G
GW±BW± B W± B W± B
G
Y
V± G
V± G Y
G±W
G± W
W± B
GGG
G
W
G± W
G± W
B
W± B R± W
B
G±W G± W G±O
G±O
W
±B W
W± GBR
Y±V L±B L
W± B
W± B
W± B
W± B
W± B
G
W± G
W± B
±PK ±STP E HS +STP
ETCRLRVREILL±
7
G± O
G± O
+PK BWRN
T
15A
STOP
F3
LH
F4
RH
FRONT
CLEARANCE LI GHT
L3
LI GHT FAI LURE SENSOR
RE AR LI GHT WARNI NG
LI GHT[ COMB. MET ER]
S12
STOP L I GHT SW
To ABS ECU<8±3><9±4>
To Shi f t Lock ECU< 15±2>
G2
GLOVE BOX
LI GHT SW
F5
LH
F6
RH
FRONT SI DE
MARKER L I GHT
L2
LI CE NCE
PLATE LI GHT
W± BW± B
W± BH9
HI GH MOUNT
STOP L I GHT
H8
HI GH MOUNT
STOP L I GHT A15
A / C C ON TR OL SW
AND RADI O SW
RADI O AND PLAYER
( w/ o CD Pl ayer )
R2
RADI O AND PLAYER
( w/ CD Pl ayer )
T1 2
TRACTI ON CUT SW AND
SEAT HEATER SW
C1 1
CI GARETTE LI GHTER
A21
A/ T I NDI CATOR LI GHT E8
ECT PATTERN
SELECT SW
T1 5
TRI P SW AND THEFT DETERRENT
I NDI CATOR LI GHT
R9
RHEOSTAT
G1
GLOVE BOX
55
13 13W± B
W± B
W± B W± B W± B
R± W
G± R
R± W G± R G±RTAI L AND
STOP LI GHT
[ REAR COMB.
LI GHT]
R1 0
LH
R1 1
RH
TAI L
ST OP
TAI L
ST OP
To Engi ne and ECT ECU< 2±3>
To Tr act i on ECU< 8±8>
To Cr ui se Cont r ol ECU< 16±4>
To Cr ui se c ont r ol
ECU< 16±4>
To Po wer Se at E CU
(Dr i ver ' s )
< 11±5>
G± W
G± W
(
* 2
)
( * 2
)
(
* 1
)
C13 , C14
ED
H
H
H
H
I3C
1
17
2345
COMBI NATI ON METER C12 , C14 IH R5 , R6
FG
12 34
5678910
12
3456
RADI O AND PLAYER
(
w/ o CD Pl ay er )
Taillight and Stop Light (
for Canada )
Illumination(
for Canada )
*2:
(
w/ o Rear Spoi l er )
*
1:
(
w/ Rear Spoi l er )
W 10 11 12 13 17 18 19 20 2112345 6789
14 15 16
17 18
1 2345 6789 10
23
22
21
20
19
15
14
13
12
11 16 C1 2 I
C1 4 H
COMBI NATI ON METER
G±W
W± L
G± O (
* 1
)
Fr o nt s i de of
r i ght f ender Fr o nt s i de o f
l ef t f ender Bac k panel cent er
RE AR LI GHT WARNI NG
LI GHT[ COMB. MET ER]
10
3H
2
3G 62
IQ1 2
IQ14
GW±G GW±G
G
W ±G
A1
A/ C CONTROL
ASSEMBLY
23G
W± GH7
HAZARD SW
R5 F G
R6
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Page 3965 of 4087
OVERALL ELECTRICAL WIRING DIAGRAM
1234
8 LEXUS SC300 (
Cont . ne xt pa ge )
4 ACC
IG1
ST1
AM1 2
1J
7 66 66 66 66
21J
5
1B
4 6666
66 66 66 2 1I
8
4 3 5 4
2
4 3
2
1 4
3
2
1 6
4
3
1
71124 1F 2F 3F
AABA A A B
C
B
A
B
A
A
A
A
A
A
BAABAABBB A A A A A B GGGF F
F
M
15 2 12 1 25 21 24 10 1 9
1 1326128 7 222 13 5 18 16 17 4 4 7IE2
1IO1
2 3
1 2
1
6
EB EA IJ M
2Bc2
12 IE2
H
4H 5H6H1H 2H3
I
2I 1J1
SFR SFL SRR SRL AST MT BSR BSM BSA
BS BM GND E2 PR VC SRC SMC SAC
MTT
BT M
EM2
BBBBBBBC
C
C
C
C
C
C
C
C
C
C
B
B
C 9IO1
EB1
6
10 IO1
3BW1 8BW1
6Bc2 5Bc2 2BW1 6BW1
7BW1
3B
1
221 1 112 2 320 741361511 7 81214 510
15 5 14 3 8 6 17
SFR SFL SRR SRL AST MT GND1 GND2 GND3 FL+ FL± FSS FR+ FR± RL+ RL± RSS RR+ RR± ALT LVL1 PKB W
B± Y
B±R
B±R R
VL
P± B
V±W R±B P
Y± B
LG
LG±B P± L
P± G
V±R
L
GR B
R± W
W±B (
SHIELDED )(
SHI ELDED)
B± R B± R
W± B L± Y G
V±Y
R± W
W± B MTT SR MR TMR E2 PR VC SRC SMC SAC TSR R± BAT I G STPTS WA TC D/G ABSO
RLORRO
FL OFRO
BRFA THFA
BRCBRP
TRCO NL PW±LR
Y
W
W
L±W B±R
R±B
L
Y R
V±Y
V±Y
V±Y
W
B±Y
R
R±W R
B±R
B±R
R
G± W
G±W B±Y
L±Y
R± B
Y
G
( SHI ELDED )
W
B
R
V± Y
V
V± W R± W R±W R±W
B±R V±Y W
W± L
V L
P±B
W± B W± B W± B
L±W Y± G
P± B P
B± Y
Y
L±W
L
W± B
W± B W± B
W
B
O±L
W± L W
O
O
W
W
O
L±GL±Y
L±G
L±Y Y±G Y±G
B
R±W
LR±W
B±Y V±R P± GP± L
LG±B LG
Y±B
P
R± B R±B V± W B±R B±R
V± Y
W±B W±B
(SHIELDED )
(
SHI EL DED )
(
SHI ELDED )I15
IGNITION SW
40A
IGSW
4 2 1456
R
T5
TRACTION PUMP
A N D MOT ORTRACTI ON BRAKE
ACTUATOR
ABS AND T RACTI ON ECU
60A MAIN
30A ABS NO. 2 60A ABS
NO. 1100A AM1
ABS
ACTUATOR
RELAY
ABS MOTOR
RELAY
TRACTION MOTOR
RELAY
TRACTION BRAKE
MAI N RELAY
10A DOME
6 BATTERY AB S A CT UA TOR
(SHI ELDED ) W± B
A7
ABS SPEED SENSOR
FRONT LH
A8
ABS SPEED SENSOR
FRONT RHA30
ABS SPEED SENSOR
REAR LH
F9
FUSE BLOCK
B±Y
From Stop Light
SW<4±6><5±6>
5BW1
A31
ABS SPEED SENSOR
REAR RH
From Alternator
º Lº < 1±2>
Power
Source ABS and Traction Control
B±R15A ECU±IGY
23 22 16 9 20 10 19
T3 ,T4
FG
(
SHI ELDED )
A4 , A5 , A6
HJ I A2 4 A , A25 B , A2 6 C
W
120A ALT
R
Fro nt s id e of
left fenderRight kick panel
Fr ont side of
right f ender
1
3
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Page 3966 of 4087
567 8
8LEXUSSC300(
Cont ' d )
22 11 4 14 8 1716 23
1B
5
3A
6 3E
3
3B
3 1E
11 3H 12
18 IK2 15 IK2 12 IJ 2 7IO1 8IO1
9IK2 5IK2 4IK2
2IK2 10IK1
23 E BRP
4E
TRCO 1D
BRC 5E
THFA 4D
BRFA 10 D
FRO 3D
FL O 12 D
RRO 5D
RLO 15 D
ABSO 8D
BAT 2E
IG1 6D
TC 16 E
TR5 11 D
IND 14 D
WT 5
K
15 K
1
K
7D P
16 D N
1EPKB
13 IK2 3H
7
From A/ T Indicat or SW
[ NEUTRAL START SW AND
BACK±UP LIGHT]< 3±7> 26 E
BCM
25 EB±
24 EB
11 E A
12 EA±
13 EACM
14 EGND
13 DCS W
3ES1
15 E
BM 2D
STP 21 E
TR2 6E
NE O 8E
VT H 19 E
VSH 10 E
IDL1 22 E
IDL2
6 2
16 IK2
13 IJ1 3H
14
1E
18 3A
2
1J
1
IJ IF EE
213645
BCM B± B A A± ACM 1J
52
3A
4
3D
13 1E
12 2 13 14
5EE1
1
L
To Engine and
ECT ECU< 2±8>
10A
GA U GE 7. 5A
TRAC
From Stop Light SW
<5±6><4±6>
From Trottle Position
Sensor< 2±8>
FromSubThrottlePosition
Sensor< 2±8>
WB±Y
L
V± R
P±G P±L
LG±B LG
Y±B P
R± B
V±W P±B L
V
R
B± R B± R
R±W L
GR
B
R±W GR
L V± W
P±B
WA TC TC ABS W TRC
B±Y
V± R
P±G P±L
LG±B LG
Y±B
P
R±B
R
B±R RR
R±B
B±Y
W
L±R Y
Y
L±R
G±W
Y± RP±L
V±Y
Y±L R
R±B
BR
Y± R
W± B
BR
G
W L
R Y B
B
W± B Y± R
W±B
W±B
W± B
BR L
GR
L
L
P±B
L±Y W
LG±R LG±R W P±B
V± W L±G
W
P±B
P±B
P±B
W±B
R± W
W
B±Y
TS WB
C3
CHECK
CONNECTOR T6
TDCL
(
Total Diagnstic
Communic ation Link )
TRACTION ECU ABS WARNI NG AND
TRACTION OFF INDICATOR
AND TRA CT I ON I NDI CA TOR
LI GHTABS
TRAC OFF
S8
SUB THROTTL E
ACTUATOR
T12
TRACTION CUT SW (
SHI ELDED )
ABS and Traction Control
To Parking Brake SW
(
Canada )
< 21±2>
To Brake Fluide Level SW
( USA )
< 21±2>
To Parking Brake SW
< 21±3>
C1 3 , C14 KL
T1 3 , T1 4 DE 7IJ2
L±R
ABS AND TRACTION ECU TRACTION ECUABS WARNING AND TRACTION OFF INDICATOR AND
TRA CT I ON I NDI CA TOR L I GHT
Right k ick panel Left k ickpanelRea r
side of
cylinder
head LH
G±W
E
E1
20
To Engine and
ECT ECU< 2± 8> BRBR
BR
1234 67891011
14 15 16 17 18 24
512
25 26
20
19 21 22 23 13 12345 7 891011
1214 15 16 17 18 22
6
19 20 21
13 12345678
16
15
14
13
12
11
10
9 12345678
16
15
14
13
12
11
10
9 1234 67891011
14 15 16 17 18 24
512
25 26
20
19 21 22 23 13
A
A2 4 B A2 5 CA26 DT13 DARK GRAY E T1 4 DARK GRAY
12 34 56 78
910 111213 141516 1718
17 18
1 2345 6789 10
23
22
21
20
19
15
14
13
12
11 16
K
C13 L C14 123
456
12
34
F
T 3 BLACK G T4 BLACK
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