power steering LEXUS LS430 2003 Factory Repair Manual

When there is a malfunction in the contact point of the terminals or installation problems with parts,
removal and installation of the suspected problem parts may return the system to the normal condition
either completely or temporarily.
In order to determine the malfunctioning area, be sure to check the conditions at the time the malfunction
occurred, such as by DTC output and the freeze frame data output, and record it before disconnecting
each connector or removing and installing parts.
Since the ABS with EBD & BA & TRAC & VSC systems may be influenced by a malfunction in the
other systems, be sure to check for DTCs in the other systems.
Be sure to remove and install the skid control ECU, ABS & TRAC actuator and each sensor with the IG
switch OFF unless specified in the inspection procedure.
When removing and installing the skid control ECU, ABS & TRAC actuator and each sensor, be sure to
check that the normal display is output in test mode inspection and in DTC output inspection after
installing all the parts.
After replacing the yaw rate sensor and/or the brake actuator assembly, make sure to perform yaw rate
sensor and deceleration sensor zero point calibration.
(see CALIBRATION
)
CAN communication system is used for the data communication between the skid control ECU (included
in the actuator), the steering angle sensor, and the yaw rate sensor (the deceleration sensor is included). If
there is trouble in the CAN communication line, the DTC in the communication line is output.
If the DTC in the CAN communication line is output, repair the malfunction in the communication line
and troubleshoot the ABS with EBD & BA & TRAC & VSC systems under the condition that data
communication is normal.
Since the CAN communication line has its own length and route, it can not be repaired temporarily with
the bypass wire, etc.
SYSTEM NAME REFERENCE
System NameSee Procedure
Front Power Seat Control SystemINITIALIZATION

For details of each code, go to Fig. 16
DTC C1715, DTC C1716, DTC C1717,
DTC C1791, DTC C1792, DTC C1793
RIGHT FRONT ACCELERATION SENSOR CIRCUIT
DTC C1725, DTC C1726, DTC C1727,
DTC C1728
RIGHT FRONT ABSORBER CONTROL ACTUATOR
CIRCUIT
DTC C1735EXHAUST SOLENOID VALVE CIRCUIT
DTC C1737, DTC C1738, DTC C1739,
DTC C1740
RIGHT FRONT HEIGHT CONTROL SOLENOID
VALVE CIRCUIT
DTC C1741AIR SUS RELAY CIRCUIT
DTC C1742HEIGHT CONTROL COMPRESSOR CIRCUIT
DTC C1751, DTC C1752CONTINUOUS ELECTRIC CURRENT TO HEIGHT
CONTROL COMPRESSOR
DTC C1761ECU MALFUNCTION
DTC C1774POWER SOURCE CIRCUIT
DTC C1776SPEED SENSOR CIRCUIT
DTC C1777STEERING ANGLE SENSOR CIRCUIT
DTC C1786HEIGHT CONTROL SWITCH CIRCUIT (TEST
DIAGNOSIS)
DTC C1787ABSORBER CONTROL SWITCH CIRCUIT (TEST
DIAGNOSIS)

b. Turn the ignition switch to the ON position and turn the hand-held tester main switch on.
c. Select the item below in the DATA LIST and read its value displayed on the hand-held tester.
AIR SUS:
Fig. 125: Data List Value Description

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
d. Check that the steering wheel turning angle value of the steering angle position sensor displayed on
the hand-held tester changes when turning the steering wheel.
Standard:
Steering wheel turning angle value changes.
NG: Go to step 2
OK: REPLACE SUSPENSION CONTROL ECU (SEE REPLACEMENT
)
2.CHECK DIAGNOSTIC CODE OUTPUT
a. Check if the normal system code is output in the CAN communication system (SEE
SUSPENSION CONTROL ECU COMMUNICATION STOP MODE
).
OK:
No DTC is output in the CAN communication system.
NG: REPAIR CIRCUIT INDICATED BY OUTPUT CODE
OK:Go to next step
3.CHECK HARNESS AND CONNECTOR (STEERING SENSOR POWER SOURCE)
a. Disconnect the steering sensor S16 connector.
b. Turn the ignition switch to the ON position.
c. Measure the voltage according to the value (s) in the table below.
TESTER CONNECTION STANDARD SPECIFIED CONDITION
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Tester ConnectionSpecified Condition
S16-1 (IG1) - S16-2 (ESS)10 to 14 V
S16-3 (BAT) - S16-2 (ESS)10 to 14 V

AUTOMATIC TRANSMISSION DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
CIRCUIT, B+ SHORT CIRCUIT IN ABS MOTOR
RELAY CIRCUIT, SHORT CIRCUIT IN ABS
MOTOR FAIL SAFE RELAY CIRCUIT
DTC C0278/11, C0279/12 OPEN/SHORT CIRCUIT IN ABS SOLENOID
RELAY CIRCUIT
DTC C1201/51 ENGINE CONTROL SYSTEM MALFUNCTION
DTC C1203/53 ECM COMMUNICATION CIRCUIT
MALFUNCTION
DTC C1210/36, C1336/39 ZERO POINT CALIBRATION OF YAW
RATE/DECELERATION SENSOR UNDONE
DTC C1223/43 ABS CONTROL SYSTEM MALFUNCTION
DTC C1231/31 MALFUNCTION IN STEERING ANGLE
SENSOR CIRCUIT
DTC C1232/32, C1234/34, C1243/43, C1244/44,
C1245/45, C1381/97
MALFUNCTION IN DECELERATION/YAW
RATE SENSOR, OPEN OR SHORT IN
DECELERATION SENSOR CIRCUIT,
MALFUNCTION IN POWER SUPPLY VOLTAGE
YAW/DECELERATION SENSOR
DTC C1235/35, C1236/36, C1238/38, C1239/39 FOREIGN MATTER IS ATTACHED ON TIP OF
RIGHT/LEFT FRONT/REAR SENSOR
DTC C1241/41 LOW BATTERY POSITIVE VOLTAGE
DTC C1246/46 MALFUNCTION IN MASTER CYLINDER
PRESSURE SENSOR
DTC C1249/49 OPEN CIRCUIT IN STOP LIGHT SWITCH
CIRCUIT
DTC C1251/51 PUMP MOTOR IS LOCKED/OPEN CIRCUIT IN
PUMP MOTOR GROUND
DTC C1267/67 Brake Pedal Load Sensing Switch
DTCDescription
DTC P0705, P0850 TRANSMISSION RANGE SENSOR CIRCUIT
MALFUNCTION (PRNDL INPUT),
PARK/NEUTRAL SWITCH INPUT CIRCUIT
DTC P0710, P0712, P0713 TRANSMISSION FLUID TEMPERATURE
SENSOR "A" CIRCUIT LOW/HIGH INPUT
DTC P0711 TRANSMISSION FLUID TEMPERATURE
SENSOR "A" PERFORMANCE
DTC P0717 TURBINE SPEED SENSOR CIRCUIT NO
SIGNAL
DTC P0724 BRAKE SWITCH "B" CIRCUIT HIGH
DTC P0729 GEAR 6 INCORRECT RATIO

ENGINE IMMOBILIZER DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION (W/SMART
KEY)
ENGINE IMMOBILIZER DIAGNOSTIC TROUBLE CODES (DTC) IDENTIFICATION (W/O
SMART KEY)
C1714, DTC C1714 CIRCUIT
DTC C1715, DTC C1716, DTC C1717, DTC
C1791, DTC C1792, DTC C1793
RIGHT FRONT ACCELERATION SENSOR CIRCUIT
DTC C1725, DTC C1726, DTC C1727, DTC
C1728
RIGHT FRONT ABSORBER CONTROL ACTUATOR
CIRCUIT
DTC C1735 EXHAUST SOLENOID VALVE CIRCUIT
DTC C1737, DTC C1738, DTC C1739, DTC
C1740
RIGHT FRONT HEIGHT CONTROL SOLENOID
VALVE CIRCUIT
DTC C1741 AIR SUS RELAY CIRCUIT
DTC C1742 HEIGHT CONTROL COMPRESSOR CIRCUIT
DTC C1751, DTC C1752 CONTINUOUS ELECTRIC CURRENT TO HEIGHT
CONTROL COMPRESSOR
DTC C1761 ECU MALFUNCTION
DTC C1774 POWER SOURCE CIRCUIT
DTC C1776 SPEED SENSOR CIRCUIT
DTC C1777 STEERING ANGLE SENSOR CIRCUIT
DTC C1786 HEIGHT CONTROL SWITCH CIRCUIT (TEST
DIAGNOSIS)
DTC C1787 ABSORBER CONTROL SWITCH CIRCUIT (TEST
DIAGNOSIS)
DTCDescription
DTC B2780 PUSH SWITCH/KEY UNLOCK WARNING
SWITCH MALFUNCTION
DTC B2793 TRANSPONDER CHIP MALFUNCTION
DTC B2794 UNMATCHED ENCRYPTION CODE
DTC B2795 UNMATCHED KEY CODE
DTC B2797 COMMUNICATION MALFUNCTION NO.1
DTC B2799 ENGINE IMMOBILIZER SYSTEM
MALFUNCTION
DTCDescription
DTC B2780 PUSH SWITCH/KEY UNLOCK WARNING
SWITCH MALFUNCTION
DTC B2793 TRANSPONDER CHIP MALFUNCTION

MULTIPLEX COMMUNICATION SYSTEM DIAGNOSTIC TROUBLE CODE (DTC)
IDENTIFICATION
DTC B2419 BEAN COMMUNICATION MALFUNCTION
DTC B2420 AFS ECU MALFUNCTION
DTCDescription
DTC B1205 AFS ECU COMMUNICATION STOP
DTC B1211 DRIVER DOOR ECU COMMUNICATION STOP
DTC B1212 FRONT PASSENGER DOOR ECU COMMUNICATION STOP
DTC B1213 TILT AND TELESCOPIC ECU COMMUNICATION STOP
DTC B1214, B1215 DOOR SYSTEM COMMUNICATION BUS MALFUNCTION (+B SHORT)/
(GND SHORT)
DTC B1216 REAR RIGHT DOOR ECU COMMUNICATION STOP
DTC B1217 REAR LEFT DOOR ECU COMMUNICATION STOP
DTC B1219 REAR SEAT SWITCH COMMUNICATION STOP
DTC B1248 AVC-LAN COMMUNICATION IMPOSSIBLE
DTC B1262 A/C ECU COMMUNICATION STOP
DTC B1263 LUGGAGE ROOM JUNCTION BLOCK ECU COMMUNICATION STOP
DTC B1266, B1267 INSTRUMENT PANEL SYSTEM COMMUNICATION BUS MALFUNCTION
(+B SHORT)/(GND SHORT)
DTC B1269 THEFT DETERRENT ECU COMMUNICATION STOP
DTC B1271 COMBINATION METER ECU COMMUNICATION STOP
DTC B1272 POWER SEAT ECU COMMUNICATION STOP
DTC B1273 SLIDING ROOF ECU COMMUNICATION STOP
DTC B1275 ACCESSORY BUS BUFFER COMMUNICATION STOP
DTC B1277 CENTER INTEGRATION ECU COMMUNICATION STOP
DTC B1278 COMBINATION SWITCH ECU COMMUNICATION STOP
DTC B1279 RAIN SENSOR COMMUNICATION STOP
DTC B1281 AIRBAG ECU COMMUNICATION STOP
DTC B1283 DRIVER SIDE JUNCTION BLOCK ECU COMMUNICATION STOP
DTC B1284 PASSENGER SIDE JUNCTION BLOCK ECU COMMUNICATION STOP
DTC B1285 STEERING PAD SWITCH COMMUNICATION STOP
DTC B1291, B1292 LIGHT SYSTEM COMMUNICATION BUS MALFUNCTION (+B SHORT)/
(GND SHORT)
DTC B1294 IMMOBILIZER ECU COMMUNICATION STOP
DTC B1296 FRONT LIGHT ECU COMMUNICATION STOP
DTC B1297 CLEARANCE SONAR ECU COMMUNICATION STOP
DTC B1298 REAR RIGHT SEAT ECU COMMUNICATION STOP
DTC B1299 REAR LEFT SEAT ECU COMMUNICATION STOP

PRE-COLLISION SAFETY SYSTEM DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
POWER DOOR LOCK CONTROL SYSTEM DIAGNOSTIC TROUBLE CODE (DTC)
IDENTIFICATION
POWER TILT & TELESCOPIC STEERING COLUMN DIAGNOSTIC TROUBLE CODE (DTC)
IDENTIFICATION
DTCDescription
DTC B2000 RIGHT SIDE MOTOR LINE MALFUNCTION HI
DTC B2001 RIGHT SIDE MOTOR LINE MALFUNCTION LO
DTC B2002 RIGHT SIDE MOTOR LINE MALFUNCTION
OPEN
DTC B2005 LEFT SIDE MOTOR LINE MALFUNCTION HI
DTC B2006 LEFT SIDE MOTOR LINE MALFUNCTION LO
DTC B2007 LEFT SIDE MOTOR LINE MALFUNCTION
OPEN
DTC B2015, B2016, B2020, B2021, B2025,
B2026, B2027, B2030, B2031, B2032, B2035,
B2036, B2040, B2041, B2047
RIGHT/LEFT SIDE UPPER/LOWER MOS
MALFUNCTION OPEN, RIGHT SIDE CURRENT
DETECTION CIRCUIT MALFUNCTION HI/LO,
RIGHT/LEFT SIDE OVER-CURRENT
MALFUNCTION, LEFT SIDE CURRENT
DETECTION CIRCUIT MALFUNCTION HI/LO,
POWER SUPPLY RELAY ADHERENCE
MALFUNCTION, POWER SUPPLY RELAY
MALFUNCTION OPEN, EEPROM
MALFUNCTION, FALL OF THE RAISED
VOLTAGE, PRE-COLLISION SAFETY ECU
INNER CIRCUIT MALFUNCTION
DTC B2043 FALL OF THE +B VOLTAGE
DTC B2059 VEHICLE SPEED MALFUNCTION OF
DISTANCE CONTROL ECU
DTC B2064 VEHICLE TYPE SIGNAL MALFUNCTION
DTCDescription
DTC B1222 DOOR LOCK SWITCH CIRCUIT ON DRIVER
DOOR
DTC B1224 DOOR LOCK SWITCH CIRCUIT ON
PASSENGER DOOR
DTCDescription

POWER WINDOW CONTROL SYSTEM DIAGNOSTIC TROUBLE CODE (DTC)
IDENTIFICATION
STEERING LOCK SYSTEM DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
DTC B2602 KEY UNLOCK WARNING SWITCH CIRCUIT
MALFUNCTION
DTC B2610 TILT POSITION SENSOR OR TILT MOTOR
CIRCUIT MALFUNCTION
DTC B2611 TELESCOPIC POSITION SENSOR OR
TELESCOPIC MOTOR CIRCUIT
MALFUNCTION
DTC B2620 ECU POWER SOURCE CIRCUIT
MALFUNCTION
DTC B2621 COMMUNICATION INTERRUPTION
DTCDescription
DTC B1221 POWER WINDOW SWITCH CIRCUIT ON DRIVER DOOR
DTC B1223 POWER WINDOW SWITCH CIRCUIT ON PASSENGER DOOR
DTC B1226 POWER WINDOW SWITCH CIRCUIT ON REAR LEFT DOOR
DTC B1225 POWER WINDOW SWITCH CIRCUIT ON REAR RIGHT DOOR
DTC B1231, B1232 JAM PROTECTION LIMIT SWITCH CIRCUIT ON DRIVER DOOR, JAM
PROTECTION PULSE SWITCH CIRCUIT ON DRIVER DOOR
DTC B1233, B1234 JAM PROTECTION LIMIT SWITCH CIRCUIT ON PASSENGER DOOR, JAM
PROTECTION PULSE SWITCH CIRCUIT ON PASSENGER DOOR
DTC B1237, B1238 JAM PROTECTION LIMIT SWITCH CIRCUIT ON REAR LEFT DOOR, JAM
PROTECTION PULSE SWITCH CIRCUIT ON REAR LEFT DOOR
DTC B1235, B1236 JAM PROTECTION LIMIT SWITCH CIRCUIT ON REAR RIGHT DOOR,
JAM PROTECTION PULSE SWITCH CIRCUIT ON REAR RIGHT DOOR
DTCDescription
DTC B2775 INTERIOR VERIFICATION ABNORMAL (TO
THEFT DETERRENT ECU)
DTC B2776 STEERING LOCK MOTOR MALFUNCTION
DTC B2777 +B CIRCUIT MALFUNCTION
DTC B2778 INTERLOCK CABLE MALFUNCTION
DTC B2780 PUSH SWITCH/KEY UNLOCK WARNING
SWITCH MALFUNCTION
DTC B2799 ENGINE IMMOBILIZER SYSTEM
MALFUNCTION

MOTORS LOCATION
Navigation ECUFig. 4 .
Passenger Side J/B ECUAt right kick panel. See Fig. 17 .
Power Tilt & Power Telescopic ECUBehind left side of dash. See Fig. 17 .
PPS ECURight side of dash. See Fig. 17 .
Rear Door LH ECUInside left rear door. See Fig. 4 .
Rear Door RH ECUInside right rear door. See Fig. 4 .
Rear LH Seat ECUBehind left side of rear seat back. See Fig. 32 .
Rear RH Seat ECUBehind right side of rear seat back. See Fig. 32 .
Seat Belt Control ECULeft side of luggage compartment. See Fig. 4 .
Seat Climate Controller Front LH (Seat Back)In driver's seat back. See Fig. 31 .
Seat Climate Controller Front RH (Seat Back)In passenger's seat back. See Fig. 31 .
Seat Climate Controller Rear LH (Seat Back)In left rear seat back. See Fig. 32 .
Seat Climate Controller Rear LH (Seat Cushion)In left rear seat cushion. See Fig. 32 .
Seat Climate Controller Rear RH (Seat Back)In right rear seat back. See Fig. 32 .
Seat Climate Controller Rear RH (Seat Cushion)In right rear seat cushion. See Fig. 32 .
Shift Lock Control ECUBelow shift lever, in center console. See Fig. 18 .
Skid Control ECU W/ActuatorBehind left side of dash. See Fig. 1 .
Steering Lock ECULeft side of dash. See Fig. 18 .
Stereo Component TunerOn lower right side of luggage compartment. See
Fig. 4
.
Television Camera ECURight rear of luggage compartment. See Fig. 4 .
Theft Deterrent ECUBehind upper right center of dash. See Fig. 18 .
Transponder Key ComputerBehind upper center of dash. See Fig. 18 .
Vibration Seat ECU LHBehind left rear seat back. See Fig. 32 .
Vibration Seat ECU RHIn rear seat assembly. See Fig. 32 .
ComponentLocation
Air Inlet Control Servo MotorRight side of dash. See Fig. 2 .
Air Mix Control Servo Motor (Driver Side)Center of dash. See Fig. 2 .
Air Mix Control Servo Motor (Front Passenger
Side)Right side of dash. See Fig. 2 .
Air Vent Mode Control Servo Motor (Driver Side)Center of dash. See Fig. 2 .
Air Vent Mode Control Servo Motor (Front
Passenger Side)Center of dash. See Fig. 2 .
Blower MotorBehind lower right side of dash. See Fig. 2 .
Cool Air Bypass Servo Motor (Driver's Side)Left side of dash. See Fig. 2 .
Cool Air Bypass Servo Motor (Front Passenger
Side)Right side of dash. See Fig. 2 .
Front Wiper MotorBelow left side of windshield. See Fig. 13 .

Control)
Power Seat Position Sensor (Driver's Seat Cushion
Control)In lower left side of driver's seat cushion. See Fig.
31 .
Power Seat Position Sensor (Driver's Seat Front
Vertical Control)At lower right side of driver's seat cushion. See Fig.
31 .
Power Seat Position Sensor (Driver's Seat Lifter
Control)In driver's seat assembly. See Fig. 31 .
Power Seat Position Sensor (Driver's Seat Reclining
Control)In lower left side of driver's seat. See Fig. 31 .
Power Seat Position Sensor (Driver's Seat Slide
Control)Lower left side of driver's seat. See Fig. 31 .
Power Seat Position Sensor (Rear Passenger's LH
Seat Slide Control)In left side of rear seat. See Fig. 32 .
Power Seat Position Sensor (Rear Passenger's RH
Seat Slide Control)In right side of rear seat. See Fig. 32 .
Rain SensorNear top center of windshield. See Fig. 29 .
Side Air Bag Sensor Front LHNear base of left "B" pillar. See Fig. 30 .
Side Air Bag Sensor Front RHNear base of right "B" pillar. See Fig. 30 .
Side Air Bag Sensor Rear LHNear lower rear of left rear door opening. See Fig.
30 .
Side Air Bag Sensor Rear RHNear lower rear of right rear door opening. See Fig.
30 .
Smoke SensorCenter rear of vehicle. See Fig. 30 .
Steering SensorInside top of steering column. See Fig. 17 .
Telescopic Motor & Position SensorInside base of steering column. See Fig. 2 .
Throttle Position Sensor & MotorOn throttle body. See Fig. 15 .
Tilt Motor & Position SensorInside base of steering column. See Fig. 2 .
Turbine Speed SensorIn transmission. See Fig. 15 .
Ultrasonic Sensor (Front Left)Behind front bumper fascia. See Fig. 15 .
Ultrasonic Sensor (Front Left Center)Behind front bumper fascia. See Fig. 15 .
Ultrasonic Sensor (Front Left Side)Behind front bumper fascia. See Fig. 15 .
Ultrasonic Sensor (Front Right)Behind front bumper fascia. See Fig. 15 .
Ultrasonic Sensor (Front Right Center)Behind front bumper fascia. See Fig. 15 .
Ultrasonic Sensor (Front Right Side)Behind front bumper fascia. See Fig. 15 .
Ultrasonic Sensor (Rear Left)Behind rear bumper fascia. See Fig. 30 .
Ultrasonic Sensor (Rear Left Center)Behind rear bumper fascia. See Fig. 30 .
Ultrasonic Sensor (Rear Right)Behind rear bumper fascia. See Fig. 30 .
Ultrasonic Sensor (Rear Right Center)Behind rear bumper fascia. See Fig. 30 .
Vapor Pressure SensorBelow right rear of vehicle. See Fig. 30 .
Vehicle Speed SensorOn transmission. See Fig. 15 .
VVT Sensor LHOn left side of engine. See Fig. 15 .
VVT Sensor RHOn right side of engine. See Fig. 15 .