1991 LEXUS SC400 engine

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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125
P 5 POWER WINDOW MASTER AND DOOR LOCK CONTROL SW LH
4±GROUND: APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
8±GROUND: ALWAYS CONTINUITY
10±GROUND: APPROX. 12 VOLTS WITH IGNITION SW ON AND MASTER SW (DRIVER'S WINDOW) AT UP POSITION
9±GROUND: APPROX. 12 VOLTS WITH IGNITION SW ON AND MASTER SW (DRIVER'S WINDOW) AT DOWN OR AUTO DOWN
POSITION
WINDOW LOCK SW
OPEN WITH WINDOW LOCK SW AT LOCK POSITION
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
D1029P 529T 8B29
D1129P 629T 9A29
P 429P 729
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
1D20FRONT DOOR LH WIRE
1H
1I20COWL WIRE1J20COWL WIRE
1K
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IF236FRONT DOOR LH WIRE AND COWL WIRE (LEFT KICK PANEL)
IP138FRONT DOOR RH WIRE AND COWL WIRE (RIGHT KICK PANEL)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IF36LEFT KICK PANEL
IJ36RIGHT KICK PANEL
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
B 440FRONT DOOR LH WIRE
SERVICE HINTS
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11015
14
13 12
12345 123
GRAY GRAY
C14 P 1 P 2 S 3
X
2 2
BA
S22 S23
187
THE PPS (HYDRAULIC REACTION TYPE) CONTROLS THE HYDRAULIC PRESSURE APPLIED\
TO THE HYDRAULIC REACTION
CHAMBER IN THE GEAR BOX CONTROL UNIT USING THE PPS ECU, TO CHANGE THE STEERING FORCE AND PROVIDE OPTIMUM
STEERING FEELING AT ANY VEHICLE SPEED AND UNDER ANY STEERING CONDITIONS.
(PPS OPERATION)
WHEN THE IGNITION SW IS TURNED ON THE STARTING CURRENT FLOWS FROM THE ECU±IG FUSE TO TERMINAL 4 OF THE PPS
ECU. THE SPEED SENSOR MONITORS THE VEHICLE SPEED AND TRANSMITS CONTROL SIGNALS TO TERMINAL 3 OF THE ECU.
WHEN THE VEHICLE SPEED IS LOW, THE PPS ECU SENDS A HIGHER±VOLTAGE FROM TERMINAL 1 OF THE ECU " TERMINAL 1 OF
THE SOLENOID VALVE " TERMINAL 2 " TERMINAL 5 OF THE ECU " TERMINAL 2 " GROUND, INCREASING THE SOLENOID VALVE
OPENING ANGLE TO PROVIDE COMFORTABLE STEERING OPERATION. WHEN THE VEHICLE SPEED IS HIGH, THE PPS ECU
DECREASES THE SOLENOID VALVE OPENING ANGLE BY REDUCING THE VOLTAGE TO THE VALVE TO PROVIDE RESPONSIVE
STEERING FEELING.
P 1 PPS SOLENOID
1±2 : APPROX. 7.7
(25 °C, 77°F)
P 2 PPS ECU
4±GROUND : APPROX. 12 VOLTS WITH IGNITION SW AT ON POSITION
2±GROUND : ALWAYS CONTINUITY
1±5 : APPROX. 0.8A WITH VEHICLE SPEED BELOW 20 KM/H ( 12 MPH)
APPROX. 0.45A WITH VEHICLE SPEED AT 80 KM/H ( 48 MPH)
APPROX. 0.2A WITH VEHICLE SPEED ABOVE 160 KM/H ( 96 MPH)
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
C1428P 229S22B29
P 127S 327S23A29
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1E20INSTRUMENT PANEL WIRE
1H20COWL WIRE1I20COWL WIRE
3A22INSTRUMENT PANEL WIRE3D22INSTRUMENT PANEL WIRE
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IG236INSTRUMENT PANEL WIRE AND COWL WIRE (R/B NO. 5)
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)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IH36UNDER THE ASHTRAY LH
IJ36RIGHT KICK PANEL
SYSTEM OUTLINE
SERVICE HINTS
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160
POWER SEAT (w/ DRIVING POSITION MEMORY)
: PARTS LOCATION
CODESEE PAGECODESEE PAGECODESEE PAGE
B532P11B32R1932
D1030P1232R2032
D1230P1332S1232
F1932P1432S1932
N 127P1532S2029
P 329P1632S2132
P 832P1732T1029
P 932P1832T1931
P10A32P1932
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
1C20FLOOR WIRE
1D20FRONT DOOR LH WIRE
1H
1I20COWL WIRE1J20COWL WIRE
1K
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IF136FRONT DOOR LH WIRE AND COWL WIRE (LEFT KICK PANEL)IF236FRONT DOOR LH WIRE AND COWL WIRE (LEFT KICK PANEL)
IJ136ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)
IT138ENGINE WIRE AND A/C WIRE (BEHIND GLOVE BOX)
BT140FLOOR WIRE AND COWL WIRE (LEFT KICK PANEL)
BU140FLOOR WIRE AND INSTRUMENT PANEL WIRE (LEFT KICK PANEL)
BX140FLOOR NO. 3 WIRE AND COWL WIRE (RIGHT KICK PANEL)
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)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IF36LEFT KICK PANEL
IH36UNDER THE ASHTRAY LH
BK40UNDER THE CENTER PILLAR LH
BL40UNDER THE CENTER PILLAR RH
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
I 438COWL WIREB2742FRONT SEAT LH WIREI 538COWL WIREB2842FRONT SEAT LH WIRE
B 840FLOOR MAIN WIREB2942FRONT SEAT RH WIREB2642FRONT SEAT LH WIREB3042FRONT SEAT RH WIRE
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168POWER TILT AND POWER TELESCOPIC
: RELAY BLOCKS
CODESEE PAGERELAY BLOCKS (RELAY BLOCK LOCATION)
219ENGINE COMPARTMENT LEFT
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CODESEE PAGEJUNCTION BLOCK AND WIRE HARNESS (CONNECTOR LOCATION)
1B20ENGINE ROOM MAIN WIRE
1D20FRONT DOOR LH WIRE
1H
1I20COWL WIRE1J20COWL WIRE
1K
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CODESEE PAGEJOINING WIRE HARNESS AND WIRE HARNESS (CONNECTOR LOCATION)
IF136FRONT DOOR LH WIRE AND COWL WIRE (LEFT KICK PANEL)IF236FRONT DOOR LH WIRE AND COWL WIRE (LEFT KICK PANEL)
IJ136ENGINE WIRE AND COWL WIRE (RIGHT KICK PANEL)
IK136ENGINE WIRE AND INSTRUMENT PANEL WIRE (RIGHT KICK PANEL)
BT140FLOOR WIRE AND COWL WIRE (LEFT KICK PANEL)
BU140FLOOR WIRE AND INSTRUMENT PANEL WIRE (LEFT KICK PANEL)
Ba142FLOOR WIRE AND FRONT SEAT LH WIRE (UNDER THE FRONT LH SEAT)
: GROUND POINTS
CODESEE PAGEGROUND POINTS LOCATION
IF36LEFT KICK PANEL
IH36INSTRUMENT PANEL BRACE LH
: SPLICE POINTS
CODESEE PAGEWIRE HARNESS WITH SPLICE POINTSCODESEE PAGEWIRE HARNESS WITH SPLICE POINTS
I 3B 840FLOOR MAIN WIREI 538COWL WIREB 940FLOOR MAIN WIRE
I 838COWL WIREB2742FRONT SEAT LH WIRE
I11
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[Engine Compartment]
[Instrument Panel]
18
RELAY LOCATIONS
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19
[Body]
2: R/B No. 2Engine Compartment Left(See Page 18)
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24
RELAY LOCATIONS
6: R/B No. 6Engine Compartment Left(See Page 18)
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