ESP LEXUS SC400 1991 Service Workshop Manual

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GRAY GRAY
C14 P 1 P 2 S 3
X
2 2
BA
S22 S23
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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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