Wiring diagram LEXUS LS430 2003 Factory Owner's Guide

Fig. 129: Identifying Skid Control ECU Terminals
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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

Fig. 130: Slip Indicator Light Wiring Diagram
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INSPECTION PROCEDURE
1.PERFORM ACTIVE TEST BY HAND-HELD TESTER (SLIP INDICATOR LIGHT)

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

Fig. 131: Skid Control Buzzer Wiring Diagram
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INSPECTION PROCEDURE
HINT:
Start the inspection from step 1 when using the hand-held tester and start from step 2 when not using the hand-
held tester.
1.PERFORM ACTIVE TEST BY HAND-HELD TESTER (SKID CONTROL BUZZER)
a. Connect the hand-held tester to the DLC3.
b. Start the engine.
c. Select the item "VSC/BR WARN BUZ" in the ACTIVE TEST and operate the skid control buzzer
on the han
d-held tester.

Standard:
TESTER CONNECTION SPECIFIED CONDITION
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
Connecting terminals TC and CG of the DLC3 causes the ECU to display the DTC by blinking the ABS
warning light.
WIRING DIAGRAM
Tester ConnectionSpecified Condition
S42-30 (BZ) - Body ground1 Mohms or higher

Fig. 134: TC And CG Terminal Wiring Diagram
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INSPECTION PROCEDURE
1.INSPECT DLC3 TERMINAL VOLTAGE (DLC3 TERMINAL VOLTAGE)
a. Turn the ignition switch to the ON position.
b. Measure the voltage according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
NG: GO TO STEP 3
Tester ConnectionSpecified Condition
D1-13 (TC) - Body ground10 to 14 V

Result:
DTC OUTPUT DESCRIPTION
B: REPAIR CIRCUIT INDICATED BY OUTPUT CODE (SEE DIAGNOSTIC TROUBLE CODE
CHART )
A: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
In the sensor check mode, a malfunction of the speed sensor that cannot be detected when the vehicle is stopped
is detected while driving.
Transition to the sensor check mode can be performed by connecting terminals TS and CG of the DLC3 and
turning the ignition switch from off to the ON position.
WIRING DIAGRAM
DTC is not outputA
DTC is outputB

Fig. 138: TS And CG Terminal Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT DLC3 TERMINAL VOLTAGE (TS TERMINAL)
a. Turn the ignition switch to the ON position.
b. Measure the voltage according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
NG: Go to step 3
Tester ConnectionSpecified Condition
D1-12 (TS) - D1-4 (CG)10 to 14 V

Fig. 34: Diagnostic Trouble Code Information Chart
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HINT:
*1 If the room temperature is approximately -20°C (-4°F) or lower, DTC B1411/11 may be output even
though the system is normal.
*2 If the ambient temperature is approximately -50°C (-58°F) or lower, a DTC may be output even
though the system is normal.
*3 If the check is being performed in a dark place, DTC B1421/21 (solar sensor circuit abnormal) could
be displayed. In this case, perform DTC check again while shining a light, such as inspection light, on the
solar sensor. If DTC B1421/21 is still displayed, there could be trouble in the solar sensor circuit.
*4 If the check is being performed in a dark place, DTC B1424/24 (solar sensor circuit abnormal) could
be displayed. In this case, perform DTC check again while shining a light, such as inspection light, on the
solar sensor. If DTC B1424/24 is still displayed, there could be trouble in the solar sensor circuit.
*5 If the check is being performed in a dark place, DTC B1421/21 (solar sensor circuit abnormal) could
be displayed. In this case, perform DTC check again while shining a light, such as inspection light, on the
solar sensor. If DTC B1421/21 is still displayed, there could be trouble in the solar sensor circuit.
CIRCUIT DESCRIPTION
This sensor detects the interior temperature that is used as the basis for temperature control and sends
appropriate signals to the A/C amplifier.
Fig. 35: DTC Detection Item Trouble Area Chart

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WIRING DIAGRAM

Temperature Sensor)Thermistor)
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OK: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The sensor connected to the ECM detects fluctuations in the ambient temperature that is used for controlling the
interior temperature. The sensor sends a signal to the A/C amplifier via the ECM.
Fig. 41: DTC Detection Item Trouble Area Chart

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WIRING DIAGRAM