2003 LEXUS LS430 Control actuator

VEHICLE CONDITION / TEST DETAILS
OK: Go to next step
The operation sound of the ABS motor is heard.
OK: Go to step 2
NG: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
2.INSPECT HARNESS AND CONNECTOR (GND2 OF SKID CONTROL ECU AND BODY
GROUND)
a. Disconnect the skid control ECU connector.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
ItemVehicle Condition / Test DetailsVehicle Condition / Test Details
Turns ABS MOT RELAYABS motor relay / ON or OFFON: Motor relay ON
Tester ConnectionSpecified Condition
S42-1 (GND2) - Body groundBelow 1 ohms

Fig. 106: Identifying Skid Control ECU Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The brake pedal load sensing switch is turned on when the brake pedal is depressed with force exceeding a
predetermined level.
The skid control ECU detects if the brake pedal is depressed or not via this circuit.

Fig. 111: Identifying Skid Control ECU Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION

Fig. 114: Identifying Skid Control ECU Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
WIRING DIAGRAM

Fig. 118: Identifying Skid Control ECU Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
If the ECU stores DTC, the VSC warning light comes on in the combination meter.
The skid control ECU is connected to the combination meter via CAN and MPX communications.
WIRING DIAGRAM

Fig. 126: Inspecting Pad Wear Indicator Wire Assy
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
REAR:
HINT:
Check that there are no scratches or cracks on the pad wear indicator.
a. Remove the rear wheel RH.
b. Disconnect the pad wear indicator connector.
c. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
NG: REPLACE PAD WEAR INDICATOR WIRE ASSY
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The skid control ECU detects the TRAC control main switch ON/OFF signal and turns the TRAC OFF light
on/off.
When the TRAC control switch is pressed, the TRAC control does not operate and the TRAC OFF light comes
on.
The skid control ECU connected to the combination meter via CAN and MPX communications.
Tester ConnectionSpecified Condition
Terminal a - Terminal bBelow 1 ohms
Terminal a - Body ground1 Mohms or higher
Tester ConnectionSpecified Condition
Terminal a - Terminal bBelow 1 ohms
Terminal a - Body ground1 Mohms or higher

Fig. 129: Identifying Skid Control ECU Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: Go to next step
6.INSPECT COMBINATION METER ASSEMBLY (SEE PROBLEM SYMPTOMS TABLE
)
NG: REPAIR OR REPLACE COMBINATION METER ASSEMBLY
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The SLIP indicator blinks during TRAC & VSC operation.
The skid control ECU is connected to the combination meter via CAN and MPX communications.
WIRING DIAGRAM

B: REPAIR CAN COMMUNICATION SYSTEM (SEE PRECAUTION )
A: Go to next step
4.INSPECT COMBINATION METER ASSEMBLY (SLIP INDICATOR LIGHT) (SEE PROBLEM
SYMPTOMS TABLE )
NG: REPAIR OR REPLACE COMBINATION METER ASSEMBLY
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The skid control buzzer sounds and VSC warning (Multi-information display) comes ON during VSC
operation.
WIRING DIAGRAM
DTC is outputB