2003 LEXUS LS430 Identifying ac

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. 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. 69: Identifying Clearance Warning ECU Assy Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go To Next Step.
3.REPLACE CLEARANCE WARNING BUZZER NO.1
a. Replace clearance warning buzzer No.1 with a new one.
b. Check clearance warning buzzer No.1.
Perform ACTIVE TEST following the same procedure as for step 1.
OK: Malfunction disappears (Clearance warning buzzer No.1 sounds).
OK: NORMAL
NG: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
CIRCUIT DESCRIPTION
The clearance warning ECU assy receives the ultrasonic sensor signal to sound the clearance warning buzzer.
WIRING DIAGRAM

Fig. 71: Identifying Clearance Warning ECU Assy Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go To Next Step.
3.REPLACE CLEARANCE WARNING BUZZER NO.2
a. Replace clearance warning buzzer No.2 with a new one.
b. Check clearance warning buzzer No.2.
Perform ACTIVE TEST following the same procedure as for step 1.
OK: Malfunction disappears (Clearance warning buzzer No.2 sounds).
OK: NORMAL
NG: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE

Fig. 8: Identifying Terminals Of Climate Control ECU - LH (FR)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Disconnect the C20 and S48 blower connectors.
b. Measure the voltage and resistance of the wire harness side connectors.
Standard:
TERMINAL DESCRIPTION AND SPECIFIED CONDITION
Symbols
(Terminal
No.)Wiring
ColorTerminal
DescriptionConditionSpecified
Condition
E (C20 - 8) -
Body groundW-B -
Body
ground
GroundAlwaysBelow 1 ohms
IG (C20 -7) -
Body groundB - Body
groundPower sourceIgnition switch ON10 to 14 V
V5 (C20 - 13)
- VG (C20 - 9)GR-R - LPower supply for
volume switchAlways5 kohms
VS (C20 - 12)
- VG (20 - 9)R-B - LVolume switch signalTurn volume switch: Max0 ohms --> 5
kohms
TB5 (C20 - 4)
- TBS (20 - 3)L-Y -
BR-WSeatback temperature
sensorSeatback temperature: 10°C --
> 30°C (50°F --> 86°F)Approx. 3.7
kohms -->
Approx. 1.7