2003 LEXUS LS430 replacement

As the temperature increases, the voltage decreases.
Result:
AIR CONDITIONING AMPLIFIER (TE - SG) TEST RESULT
B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
C: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT )
Fig. 49: Inspecting Air Conditioning Amplifier (TE
- SG)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
A: Go to next step
3.INSPECT A/C EVAPORATOR TEMPERATURE SENSOR
a. Remove the A/C evaporator temperature sensor.
b. Measure the resistance according to the value (s) in table below.
NGA
OK (Checking from the PROBLEM SYMPTOM TABLE)B
OK (Checking from the DTC)C

Fig. 53: Identifying Terminals Of A/C Evaporator Temperature Sensor Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
This sensor detects the register temperature and sends the appropriate signals to the A/C amplifier.
Fig. 54: DTC Detection Item Trouble Area Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
C: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT )
A: Go to next step
2.INSPECT AIR CONDITIONING AMPLIFIER (TFACEDr - SG-3)
a. Remove the A/C amplifier with connectors still connected.
b. Turn the ignition switch to the ON position.
c. Measure the voltage according to the value (s) in the table below.
Standard:
AIR CONDITIONING AMPLIFIER (TFACEDr - SG-3) VOLTAGE
HINT:
As the temperature increases, the volta
ge decreases.
NGA
OK (Checking from the PROBLEM SYMPTOM TABLE)B
OK (Checking from the DTC)C
Tester connectionConditionSpecified condition
A13-15 (TFACEDr) - A13-10 (SG-3)Ignition switch ON at 25°C (77°F)1.8 to 2.2 V
A13-15 (TFACEDr) - A13-10 (SG-3)Ignition switch ON at 50°C (122°F)0.8 to 1.2 V

Fig. 56: Inspecting Air Conditioning Amplifier (TFACEDR - SG-3)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Result:
AIR CONDITIONING AMPLIFIER (TFACEDR - SG-3) TEST RESULT
B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
C: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT )
A: Go to next step
3.INSPECT AIR DUCT SENSOR
a. Remove the air duct sensor.
b. Measure the resistance according to the value (s) in the table below.
Standard:
NGA
OK (Checking from the PROBLEM SYMPTOM TABLE)B
OK (Checking from the DTC)C

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT )
CIRCUIT DESCRIPTION
This sensor detects the register temperature and sends the appropriate signals to the A/C amplifier.
Fig. 59: DTC Detection Item Trouble Area Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM
Fig. 60: Air Duct Sensor Circuit (Passenger Side)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.READ VALUE ON HAND-HELD TESTER

a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position and push the hand-held tester main switch on.
c. Select the item below in the DATA LIST, and read the display on the hand-held tester.
DATA LIST / AIR CONDITIONER:
DATA LIST / AIR CONDITIONER
OK:
The display is as specified in the normal condition.
Result:
AIR CONDITIONER TEST RESULT
B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
C: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT )
A: Go to next step
2.INSPECT AIR CONDITIONING AMPLIFIER (TFACEPa - SG-4)
a. Remove the A/C amplifier with connectors still connected.
b. Turn the ignition switch to the ON position.
c. Measure the voltage according to the value (s) in the table below.
Standard:
AIR CONDITIONING AMPLIFIER (TFACEPa - SG-4) VOLTAGE
HINT:
As the temperature increases, the volta
ge decreases.
ItemMeasure Item/Display (Range)Normal ConditionDiagnostic
Note
DUST
TEMP-PDuct sensor (Passenger side) / min.: -12.7°C
(9.14°F) max.: 76.55°C (169.79°F)Actual duct temperature is
displayed (Passenger side)-
NGA
OK (Checking from the PROBLEM SYMPTOM TABLE)B
OK (Checking from the DTC)C
Tester connectionConditionSpecified condition
A13-14 (TFACEPa) - A13-11 (SG-4)Ignition switch ON at 25°C (77°F)1.8 to 2.2 V
A13-14 (TFACEPa) - A13-11 (SG-4)Ignition switch ON at 50°C (122°F)0.8 to 1.2 V

Fig. 61: Inspecting Air Conditioning Amplifier (TFACEPA - SG-4)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Result:
AIR CONDITIONING AMPLIFIER (TFACEPA - SG-4) TEST RESULT
B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
C: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT )
A: Go to next step
3.INSPECT AIR DUCT SENSOR
a. Remove the air duct sensor.
b. Measure the resistance according to the value (s) in the table below.
Standard:
NGA
OK (Checking from the PROBLEM SYMPTOM TABLE)B
OK (Checking from the DTC)C

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE AIR CONDITIONING AMPLIFIER (SEE REPLACEMENT )
CIRCUIT DESCRIPTION
This sensor detects the exhaust gas (HC, CO) outside the vehicle and sends a signal to the A/C amplifier.
Fig. 64: DTC Detection Item Trouble Area Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM