LEXUS LS430 2003 Factory Repair Manual

Result:
RESULT REFERENCE
B: Go to step 5
A: Go to next step
2.CHECK SEAT CLIMATE CONTROL CONTROLLER (SEATBACK)
HINT:
When the driver side indicator is blinking, check the driver side connector. When the passenger side
indicator is blinking, check the passenger side connector.
a. Disconnect the S34 or S35 controller connector.
b. Connect the wire harness to terminal 4 (TDB-) and 5 (TDB+) of the wire harness side connector.
c. Turn the ignition switch ON.
d. Turn the climate control switch ON, then check that the climate control indicator continues
blinking.
Result:
RESULT REFERENCE
ResultProceed to
Front climate control switch indicator is blinkingA
Rear climate control switch indicator is blinkingB
ResultProceed to
Indicator continues blinkingA
Indicator turns offB

Fig. 20: Checking Seat Climate Control Controller (Seatback)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
B: REPLACE SEAT CLIMATE CONTROL CONTROLLER (SEATBACK)
A: Go to next step
3.CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL
ECU) - CLIMATE CONTROLLER)
HINT:
When the driver side indicator is blinking, check the driver side connector. When the passenger side
indicator is blinking, check the passenger side connector.
a. Disconnect the C20 or C21 blower connector.
b. Disconnect the S34 or S35 controller connector.
c. Measure the resistance of the wire harness side connectors.
Standard:

Driver side
TESTER CONNECTION AND SPECIFIED CONDITION - DRIVER SIDE
Passenger side
TESTER CONNECTION AND SPECIFIED CONDITION - PASSENGER SIDE
Tester ConnectionSpecified Condition
C20-1 (TDB-) - S34-4 (TDB-)Below 1 ohms
C20-1 (TDB-) - Body ground10 kohms or higher
C20-14 (TDB+) - S34-5 (TDB+)Below 1 ohms
C20-14 (TDB+) - Body ground10 kohms or higher
C20-1 (TDB-) - C20-14 (TDB+)10 kohms or higher
Tester ConnectionSpecified Condition
C21-1 (TDB-) - S35-4 (TDB-)Below 1 ohms
C21-1 (TDB-) - Body ground10 kohms or higher
C21-14 (TDB+) - S35-5 (TDB+)Below 1 ohms
C21-14 (TDB+) - Body ground10 kohms or higher
C21-1 (TDB-) - C21-14 (TDB+)10 kohms or higher

Fig. 21: Identifying Seat Climate Control Blower Connector And Seat Climate Controller

Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: Go to next step
4.CHECK SEAT CLIMATE CONTROL CONTROLLER (SEAT CUSHION)
HINT:
When the driver side indicator is blinking, check the driver side connector. When the passenger side
indicator is blinking, check the passenger side connector.
a. Disconnect the S48 or S49 connector.
b. Connect terminal 3 (TDC+) and 6 (TDC-) of the climate control ECU connector, as shown in the
illustration.
c. Turn the ignition switch ON.
d. Turn the climate control switch ON, and then check that the climate control switch indicator turns
off.
OK: The indicator turns off

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0b00360048004400570003002600580056004b004c00520051[)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPLACE SEAT CLIMATE CONTROL BLOWER REPAIR SEAT CLIMATE CONTROL
BLOWER (CLIMATE CONTROL ECU)
OK: REPLACE SEAT CLIMATE CONTROLLER (SEAT CUSHION)
5.CHECK SEAT CLIMATE CONTROL CONTROLLER (SEATBACK)
HINT:
When the rear LH indicator is blinking, check the rear LH connector. When the rear RH indicator is
blinking, check the rear RH connector.
a. Disconnect the S52 or S54 controller connector.
b. Connect the wire harness to terminal 4 (TDB-) and 5 (TDB+) of the wire harness side connector.
c. Turn the ignition switch ON.
d. Turn the climate control switch ON, and then check that the climate control indicator continues
blinking.

Result:
RESULT REFERENCE
Fig. 23: Checking Seat Climate Control Controller (Seatback)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
B: REPLACE SEAT CLIMATE CONTROL CONTROLLER (SEATBACK)
A: Go to next step
6.CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL
ECU) - SEAT CLIMATE CONTROLLER (SEATBACK))
HINT:
When the rear LH indicator is blinkin
g, check the rear LH connector. When the rear RH indicator is
ResultProceed to
Indicator continues blinkingA
Indicator turns offB

blinking, check the rear RH connector.
a. Disconnect the C28 or C30 blower connector.
b. Disconnect the S52 or S54 controller connector.
c. Measure the resistance of the wire harness side connectors.
Standard:
Rear LH
TESTER CONNECTION AND SPECIFIED CONDITION - REAR LH
Rear RH
TESTER CONNECTION AND SPECIFIED CONDITION - REAR RH
Tester ConnectionSpecified Condition
C28-2 (TDB-) - S52-4 (TDB-)Below 1 ohms
C28-2 (TDB-) - Body ground10 kohms or higher
C28-1 (TDB+) - S52-5 (TDB+)Below 1 ohms
C28-1 (TDB+) - Body ground10 kohms or higher
C28-1 (TDB+) - C28-2 (TDB-)10 kohms or higher
Tester ConnectionSpecified Condition
C30-2 (TDB-) - S54-4 (TDB-)Below 1 ohms
C30-2 (TDB-) - Body ground10 kohms or higher
C30-1 (TDB+) - S54-5 (TDB+)Below 1 ohms
C30-1 (TDB+) - Body ground10 kohms or higher
C30-1 (TDB+) - S30-2 (TDB-)10 kohms or higher

Fig. 24: Identifying Seat Climate Control Blower Connector Terminals And Seat Climate
Controller Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS AND CONNECTOR
OK: Go to next step
7.CHECK SEAT CLIMATE CONTROL CONTROLLER (SEAT CUSHION)
HINT:
When the rear LH indicator is blinking, check the rear LH connector. When the rear RH indicator is
blinking, check the rear RH connector.
a. Disconnect the S53 or S55 blower connector.
b. Connect the wire harness to terminal 5 (TDC+) and 4 (TDC-) of the wire harness side connector, as
shown in the illustration.
c. Turn the ignition switch ON.
d. Turn the climate control switch ON, and then check that the climate control indicator turns off.
OK: The indicator turns off