2003 LEXUS LS430 air condition

Fig. 110: Checking Harness And Connector (Cool Air Bypass Servomotor - Air Conditioning
Amplifier)
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
The air inlet servomotor is controlled by the A/C amplifier and moves the air inlet servomotor to the desired
position.
Fig. 111: DTC Detection Item Trouble Area Chart

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

Result:
ACTUATOR 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 INLET SERVOMOTOR
a. Remove the air inlet servomotor.
b. Connect the positive (+) lead from the battery to terminal 5 and negative (-) lead to terminal 4, then
check that the lever turns to the "FRESH" position smoothly.
c. Connect the positive (+) lead from the battery to terminal 4 and negative (-) lead to terminal 5, then
check that the lever turns to the "RECIRCULATION" position smoothly.
NGA
OK (Checking from the PROBLEM SYMPTOMS TABLE)B
OK (Checking from the DTC)C

Fig. 114: Inspecting Air Inlet Servomotor
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPLACE AIR INLET SERVOMOTOR
OK: Go to next step
3.CHECK HARNESS AND CONNECTOR (AIR INLET SERVOMOTOR - AIR CONDITIONING
AMPLIFIER) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Measure the resistance according to the value (s) in the table below.
Standard:
AIR INLET SERVOMOTOR - AIR CONDITIONING AMPLIFIER RESISTANCE
Tester connectionConditionSpecified condition
A36-17 (AIR) - A41-4 (REC)AlwaysBelow 1 ohms
A36-16 (AIF) - A41-5 (FRS)AlwaysBelow 1 ohms
A36-17 (AIR) - Body groundAlways10 kohms or higher
A36-16 (AIF) - Body groundAlways10 kohms or higher

Fig. 115: Checking Harness And Connector (Air Inlet Servomotor - Air Conditioning Amplifier)
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
In this circuit, the compressor assembly receives a signal on refrigerant compression required by the air
conditioning amplifier. Based on the signal, the compressor assembly changes the degree of refrigerant
compression.
Fig. 116: DTC Detection Item Trouble Area Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM
Fig. 117: Compressor Solenoid Circuit

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT AIR CONDITIONING AMPLIFIER (SOL+ - SOL-)
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 (SOL+ - SOL-) VOLTAGE
HINT:
As the temperature increases, the voltage decreases.
Result:
AIR CONDITIONING AMPLIFIER (SOL+ - SOL-) TEST RESULT
Tester connectionConditionSpecified condition
A11-6 (SOL+) - A11-7 (SOL-)Start the engine Auto switch: ONBelow 1.0 V
ANG
BOK (Checking from the PROBLEM SYMPTOMS TABLE)
COK (Checking from the DTC)

Fig. 118: Inspecting Air Conditioning Amplifier (SOL+ - SOL-)
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 COOLER COMPRESSOR ASSY (AIR CONDITIONER SOLENOID)
a. Disconnect the cooler compressor assy connector.
b. Measure the resistance according to the value (s) in the table below.
Standard:
COOLER COMPRESSOR ASSY (AIR CONDITIONER SOLENOID) RESISTANCE
Tester connectionConditionSpecified condition
1 - 2at 20°C (68°F)10 to 11 ohms

Fig. 119: Inspecting Cooler Compressor Assy (Air Conditioner Solenoid)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPLACE COOLER COMPRESSOR ASSY
OK: Go to next step
3.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - COOLER
COMPRESSOR ASSY) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Measure the resistance according to the value (s) in the table below.
Standard:
AIR CONDITIONING AMPLIFIER - COOLER COMPRESSOR ASSY RESISTANCE
Tester connectionConditionSpecified condition
A11-6 (SOL+) - C23-2AlwaysBelow 1 ohms
A11-7 (SOL-) - C23-1AlwaysBelow 1 ohms
A11-6 (SOL+) - Body groundAlways10 kohms or higher
A11-6 (SOL-) - Body groundAlways10 kohms or higher