LEXUS LS430 2003 Factory Repair Manual

AIR DUCT SENSOR RESISTANCE
HINT:
As the temperature increases, the resistance decreases.
Fig. 62: Inspecting Air Duct Sensor

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPLACE AIR DUCT SENSOR
OK: Go to next step
4.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - AIR DUCT
SENSOR) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Measure the resistance accordin
g to the value (s) in the table below.
Tester connectionConditionSpecified condition
D8-1 - D8-2at 0°C (32°F)14.5 to 19.0 kohms
D8-1 - D8-2at 25°C (77°F)4.8 to 5.2 kohms
D8-1 - D8-2at 50°C (122°F)1.6 to 2.0 kohms

Standard:
AIR CONDITIONING AMPLIFIER - AIR DUCT SENSOR RESISTANCE
Tester connectionConditionSpecified condition
A13-14 (TFACEPa) - D8-1AlwaysBelow 1 ohms
A13-11 (SG-4) - D8-2AlwaysBelow 1 ohms
A13-14 (TFACEPa) - Body groundAlways10 kohms or higher
A13-11 (SG-4) - Body groundAlways10 kohms or higher

Fig. 63: Checking Harness And Connector (Air Conditioning Amplifier - Air Duct Sensor)
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 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

Fig. 65: Emission Gas Sensor Circuit
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:
ItemMeasure Item/Display (Range)Normal ConditionDiagnostic
Note
EMISS GAS
SENSEmission gas / min.: 0 V max.:
255 VIncreases as the gas amount
increases-

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 (DGS - SG-1)
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 (DGS - SG-1) 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
A11-29 (DGS) - A13-8 (SG-1)Ignition switch ON at 10 to 35°C (50 to 95°F)1.0 to 4.5 V

Fig. 66: Inspecting Air Conditioning Amplifier (DGS - SG-1)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Result:
AIR CONDITIONING AMPLIFIER (DGS - SG-1) 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 EXHAUST GAS SENSOR
a. Remove the exhaust gas sensor.
b. After keeping to apply battery voltage between terminals 3 and 6 for more than 30 seconds,
NGA
OK (Checking from the PROBLEM SYMPTOM TABLE)B
OK (Checking from the DTC)C

measure the resistance between terminals 1 and 2.
c. Measure the resistance according to the value (s) in the table below.
Standard:
EXHAUST GAS SENSOR RESISTANCE
HINT:
<003a004b0048005100030057004b004800030056004800510056005200550003004c005600030048005b0053005200560048004700030057005200030057004b004800030048005b004b00440058005600570003004a00440056000f00030057004b004800
03005500480056004c0056005700440051004600480003004a[oes down.
Fig. 67: Inspecting Exhaust Gas Sensor

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPLACE EXHAUST GAS SENSOR
Tester connectionConditionSpecified condition
E10-1 (S.G) - E10-2 (HC)at 10 to 35°C (50 to 95°F)5 to 100 kohms

OK: Go to next step
4.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - EXHAUST GAS
SENSOR) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Measure the resistance according to the value (s) in the table below.
Standard:
AIR CONDITIONING AMPLIFIER - EXHAUST GAS SENSOR RESISTANCE
Tester connectionConditionSpecified condition
E10-1 (S.G) - A13-8 (SG-1)AlwaysBelow 1 ohms
E10-2 (HC) - A11-29 (DGS)AlwaysBelow 1 ohms
E10-1 (S.G) - Body groundAlways10 kohms or higher
A10-2 (HC) - Body groundAlways10 kohms or higher

Fig. 68: Checking Harness And Connector (Air Conditioning Amplifier - Exhaust Gas Sensor)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.