LEXUS LS430 2003 Factory Repair Manual

Fig. 60: Identifying RR IG Fuse Location
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: INSPECT FOR SHORT IN ALL COMPONENTS CONNECTED TO FUSE AND REPAIR
OR REPLACE THEM IF NEEDED, AND REPLACE FUSE
OK: Go To Next Step.
2.INSPECT CLEARANCE WARNING ECU ASSY (IG TERMINAL VOLTAGE)
a. Disconnect the C17 connector from the clearance warning ECU assy.
b. Measure the voltage according to the value (s) in the table below.

Standard:
TESTER CONNECTION SPECIFIED CONDITION
Fig. 61: Identifying C17 Connector Terminals (1 Of 2)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (CLEARANCE WARNING ECU
ASSY - BATTERY)
OK: Go To Next Step.
3.CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU ASSY - BODY
GROUND)
a. Disconnect the C17 connector from the clearance warning ECU assy.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
Tester connection (Symbols)ConditionSpecified condition
C17-5 (IG)- Body groundIG switch ON10 to 14 V

Fig. 62: Identifying C17 Connector Terminals (2 Of 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (CLEARANCE WARNING ECU
ASSY - BODY GROUND)
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
CIRCUIT DESCRIPTION
Turning this switch on activates the clearance sonar system.
WIRING DIAGRAM
Tester connection (Symbols)ConditionSpecified condition
C17-7 (MGND) - Body groundAlwaysBelow 1 ohms

Fig. 63: Clearance Sonar Main Switch Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.READ VALUE OF HAND-HELD TESTER
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position.
c. Turn the hand-held tester on.
d. Turn the clearance sonar main switch on.
e. Select the item below in the DATA LIST, and read its value displayed on the hand-held tester to
check the clearance sonar main switch.
CSONAR:

ITEM CONDITION DESCRIPTION
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
NG: Go To Next Step.
2.INSPECT CLEARANCE WARNING ECU ASSY (CLSW TERMINAL)
a. Disconnect the C17 connector from the clearance warning ECU assy.
b. Measure the voltage according to the value (s) in the table below.
Standard:
Fig. 64: Tester Connection Specified Condition Description Table

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
ConditionItemStandard
Clearance Sonar Main Switch onMAIN SW"ON" is displayed

Fig. 65: Identifying CLSW Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: REPLACE CLEARANCE WARNING ECU ASSY (SEE REPLACEMENT
)
NG: Go To Next Step.
3.CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU ASSY - BODY
GROUND)
a. Disconnect the C17 connector from the clearance warning ECU assy.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
Tester connectionConditionSpecified condition
C17-7 (MGND) - Body groundAlwaysBelow 1 ohms

Fig. 66: Identifying C17 Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (CLEARANCE WARNING ECU
ASSY - BODY GROUND)
OK: Go To Next Step.
4.INSPECT OUTER MIRROR SWITCH ASSY
a. Disconnect the O5 connector from the clearance sonar main switch.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
Tester connection (Symbols)ConditionSpecified condition
O5-3 - O5-4Clearance sonar main switch off10 kohms or higher
O5-3 - O5-4Clearance sonar main switch onBelow 1 ohms

Fig. 67: Identifying Outer Mirror Switch Assy Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPLACE OUTER MIRROR SWITCH ASSY
OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (CLEARANCE WARNING ECU
ASSY - BATTERY)
CIRCUIT DESCRIPTION
The clearance warning ECU assy receives the ultrasonic sensor signal to sound the clearance warning buzzer.
WIRING DIAGRAM

Fig. 68: Clearance Warning Buzzer No.1 Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.PERFORM ACTIVE TEST BY HAND-HELD TESTER
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position.
c. Turn the hand-held tester on.
d. Turn the clearance sonar main switch on.
e. Select the item "FRONT BUZZER" in the ACTIVE TEST, and perform it using the hand-held
tester.
f. Check that the clearance warning buzzer No.1 sounds when the ACTIVE TEST is carried out.
OK: Clearance warning buzzer No.1 sounds.
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
NG: Go To Next Step.
2.CHECK HARNESS AND CONNECTOR (CLEARANCE WARNING ECU ASSY - CLEARANCE
WARNING BUZZER NO.1)
a. Disconnect the C17 connector from the clearance warning ECU assy.
b. Disconnect the C9 connector from clearance warning buzzer No.1.

c. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
Tester connection (Symbols)ConditionSpecified condition
C17-4 (FBZ+) - C9-1AlwaysBelow 1 ohms
C17-4 (FBZ+) - Body groundAlways10 kohms or higher
C17-17 (FBZ) - C9-2AlwaysBelow 1 ohms
C17-17 (FBZ) - Body groundAlways10 kohms or higher