1991 LEXUS SC400 light

50
POWER SOURCE (Current Flow Chart)*1: USA
*2: CANADA
P18
P11
N2 N4 O2 P2 O8 P4 P6 R5 R4 P20
P14
226
154
192
154
190 68 154 90
202
202
P8
P7
184 94
O5 P5 P3
Parking Brake SW
Power Window Motor RH Power Window Motor LHOil Pressure SW
Power Seat Control SW
(for Driver's Seat)
Power Seat Control SW
(for Passenger's Seat)Power Seat ECU (Passenger's)Oxygen Sensor Sub
(for California)Power Seat Motor (for Driver's
Lumbar Support Control)O/D Main SW
Radio and Player Personal LightRadio and Player (w/ CD Player)Noise Filter
(for A/C System)Power Seat Motor (for Passenger's
Reclining Control)PPS ECU
Power Window Control SW RH
Power Window Master SW and
Door Lock Control SW LH
*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
LocationP9 P12 P10 R2
Power Seat ECU (Driver's)Noise Filter
(for Defogger System)
216 126 216 208
122


* 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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51
R5 R7S11
R11
R9 R17 R16 R18
R10 S3 S10 S13 S12
168
90
202
212
208
68
184
216
186 188
S14 T1 T6 S24
216
101 98 104 173
190
173 188
90
216 94 112
Radio and Player
(w/o CD Player)
Rheostat
S18
S17 S23
S15 S16
TDCLRear Turn Signal Light RH
[Rear Comb. Light RH] Back±Up Light LH
[Rear Comb. Light LH]
Stop Light LH
[Rear Comb. Light LH] Rear Turn Signal Light LH
[Rear Comb. Light LH]
Taillight LH
[Rear Comb. Light LH]
Back±Up Light RH
[Rear Comb. Light RH]
Stop Light RH
[Rear Comb. Light RH]
Taillight RH
[Rear Comb. Light RH]
Stop LightSeat Heater
(for Driver's Seat Back)Short Connector
Seat Heater SW (M/T) Remote Control Mirror LH Remote Control Mirror ECU
Speed Sensor No. 1
Shift Lock ECU
Stereo Power Amplifier
Theft Deterrent Horn Remote Control Mirror RH
Remote Control Mirror SW
Stop Light SWSeat Heater
(for Driver's Seat Cushion)
Seat Heater
(for Passenger's Seat Back)
Seat Heater
(for Passenger's Seat Cushion)
86 101 98 86 104 148
154
186
68
98
134
144 134
144
148
178
(4)
: R/B No. 5 (See page ) 22
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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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53
118 10422662
68
11 2
208
212
226 102
94
W7 W8 W10
Wireless Door Lock
Main SW
Wireless Door Lock ECU
Woofer Speaker Amplifier
Power Main Relay
A/C Magnetic Clutch Relay
EFI Main Relay
Heater Relay
Defogger Relay
Turn Signal Flasher
Horn Relay Diode
Cornering Light Relay Starter Relay
11 2
194 68
126 190
226
102
111
11 2
Diode
(4): R/B No. 5 (See page )
22
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56
POWER SOURCE
AM2 AM1
ACC
IG 1
IG 2
321 6 411
ST1
1B
2
1J 5
1J 6
1J 3
1J 8 1K
13
1K 4
1J
4
1B
4
1J
7 I24
I33
I11 P
N 2
3
IE1
16
IJ16
3421314 59 7
116
W
WB
B
B
B±R
B±W B±W
W±L
B
B±O P±L B
B
B
W±L R
W±R
W±R
B
W±R Y
W±L
W±R
W
W±R
B±Y
B±W P±L
B±O
B±W
B±W
B±W
B±WW
B±R
15A ECU±B
15A STOP
30A POWER
30A DOOR
TAILLIGHT
RELAY 15A TAIL
7. 5A PANEL BATTERY
15A ECU±IG
7. 5A ENGINE
20A W IPER
10A GAUGE 20A TURN
10A HEATER
7. 5A ST
7. 5A IGN 15A CIG
7. 5A RADIO NO. 2
40A
IGSW
NEUTRAL
START SW
TO ENGINE AND ECT ECUTO CRUISE CONTROL ECU
TO ABS ACTUATOR RELAY,
ABS MOTOR RELAY AND
TRACTION BRAKE
ACTUATOR RELAYTO ALTERNATOR º Bº
IGNITION SW
FUSE BLOCK
TO TRACTION MOTOR RELAY100A AM1
60A ABS NO. 1
30A INJ
120A ALT 30A AM2
30A ABS NO. 2 60A MAIN
F9
N1
I15
5
1 3
2
2
6
3 4 1
5
1 2IJ2
8 B
B±W
B
B
(
M/T )
(
M/T )
C23
CLUTCH START SW
(
A/T )
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57
87
65
43
21
10 9
12 11
14 13
21
22 21
20 19
18 17
16 15
2
2
2
2
2
2
2
2
2
2
2 2 22
2
2
2
2
2
22
2 2
2
IF 4
1B
1
4
4 2
2
4
4
EB1
3
W
B
B
B
B±R R±L
B
B
L±O R±Y L±R
WR
B±Y W
L±Y
W±L R
R
R
R±G R±B
R±W
B
R±Y
B
B
B±R
2
B
W±B B
R
1
212
1 2
2
4
3
1
1
3 43
1
3
5
2
2
4 4
3
5
3
4
20A RADIO NO. 1
25A HAZ±HORN 30A EFI
10A DOME
15A TEL
7. 5A ALT SENCING 7. 5A TRAC
HEADLIGHT
RELAY STARTER
RELAY
60A HEATER
50A DEFOGGER DEFOGGER
RE LA Y
15A SEAT±HTR
15A HEAD
(
LH±UPR )
15A HEAD (
RH±UPR )
15A HEAD (
LH )(
FOR USA )
15A HEAD (
LH±LWR )(
FOR CANADA )
15A HEAD (
RH )(
FOR USA )
15A HEAD (
RH±LWR )(
FOR CANADA )
DIMMER
RELAY
SEAT HEATER
RELAY 10A MIR±HTR
W±B I1W±B
B
(
M/T )
( A/T )
( CA NA DA )
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58
POWER SOURCE
HEADLIGHT RELAY (FOR USA)1±2 : CLOSED WITH LIGHT CONTROL SW AT HEAD POSITION OR DIMMER SW AT FLASH POSITION
HEADLIGHT RELAY (FOR CANADA) 1±2 : CLOSED WITH LIGHT CONTROL SW AT HEAD POSITION OR DIMMER SW AT FLASH POSITION
: CLOSED WITH ENGINE RUNNING AND PARKING BRAKE PEDAL RELEASED (PARKING BRAKE SW OFF)
TAILLIGHT RELAY (FOR USA) 5±3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
TAILLIGHT RELAY (FOR CANADA) 5±3 : CLOSED WITH LIGHT CONTROL SW AT TAIL OR HEAD POSITION
: CLOSED WITH ENGINE RUNNING AND PARKING BRAKE PEDAL RELEASED (PARKING BRAKE SW OFF)
IGNITION MAIN RELAY 2±1 : CLOSED WITH IGNITION KEY AT ON OR ST POSITION
I15 IGNITION SW
4±3 : CLOSED WITH IGNITION KEY AT ACC OR ON POSITION
4±2 : CLOSED WITH IGNITION KEY AT ON OR ST POSITION
11±6: CLOSED WITH IGNITION KEY AT ON OR ST POSITION
4±1 : CLOSED WITH IGNITION KEY AT ST POSITION
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C2328I1529
F 926N 127
: 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
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)
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
IF36LEFT KICK PANEL
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
I 138COWL WIREI2438ENGINE ROOM MAIN WIRE
I1138COWL WIREI3338ENGINE WIRE
SERVICE HINTS
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154
POWER SEAT (w/ DRIVING POSITION MEMORY)
PRND 2 L146578 9
GR
R±B
L
G±W G
W
A/T INDICATOR SW
[NEUTRAL START SW AND BACK±UP LIGHT SW]
N1
IT1
12
1I
10 1H 12
1C
10 1H
1
A
6
STOP A
15
P
A
3 RCL+
A
10 RCL±
B
16 SSRS
B
14 SSRR
B
6 PVCC
B
5 SSFV
B
15 SSRV
2
3 13
1265
2 13 2
13
M
B28
B26 B27
BU1
7
Ba16
Ba1
8 1 2
IJ1
10
GR
V V
V
BR±B
BR±B BR±B
BR±B
BR±B
BR±BLG
V
Y±R Y±B
V
V±W
LG±R V
Y±G V
BR±B
G±W G±W G±W W
Y
GR
GR
Y
Y
VV LG±R
Y±G
V±W
Y±B
Y±R LG
FROM POWER SOURCE SYSTEM
(
SEE PAGE 56 )
15A
STOP 10A
GAUGE
STOP LIGHT
SW
POWER SEAT ECU
(FOR DRIVE R' S SEA T )
SLIDE
POSITION
SENSOR
( FOR
DRIVE R' S SEA T )POWER SEAT MOTOR
(
FOR DRIVER' S SEAT
RECLINING MOTOR
CONTROL ) FRONT
VERTICAL
POSITION
SENSOR
RE AR
VEATICAL
POSITION
SENSOR
S20
P16 F19 R19
P10 , P 1 1
S12
AB
B261
B
( M/T )
PARKING
BRAKE SW
P
3 (
A/T )
BR±B
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