DTC P0095 P0097 P0098 2AD-FHV

DESCRIPTION

The diesel turbo Intake Air Temperature (IAT) sensor is built into the charge air cooler and senses the IAT. A built-in thermistor in the sensor changes its resistance value according to the intake air temperature. The lower the intake air temperature, the greater the thermistor resistance value. The higher the intake air temperature, the lower the thermistor resistance value (see Fig. 1).
The sensor is connected to the ECM. The 5 V power source voltage in the ECM is applied to the sensor from terminal THIA via resistor R. Resistor R and the sensor are connected in series. When the resistance value of the sensor changes in accordance with changes in the IAT, the potential at terminal THIA also changes. Based on this signal, the ECM corrects the fuel injection volume to improve driveability with a cold engine.

Toyota fault code list DTC P0095 DTC P0097 DTC P0098

DTC No.	DTC Detection Condition	Trouble Area
P0095	Open or short in diesel turbo IAT sensor circuit for 0.5 seconds (1 trip detection logic)	Open or short in diesel turbo IAT sensor circuit Diesel turbo IAT sensor ECM
P0097	Short in diesel turbo IAT sensor circuit for 0.5 seconds (sensor resistance value less than 25 ? [sensor output voltage less than 0.05 V]) (1 trip detection logic)	Open or short in IAT sensor circuit Diesel turbo IAT sensor ECM
P0098	Open in diesel turbo IAT sensor circuit for 0.5 seconds (sensor resistance value more than 156 k? [sensor output voltage more than 4.9 V]) (1 trip detection logic)	Open or short in IAT sensor circuit Diesel turbo IAT sensor ECM

 

WIRING DIAGRAM

 

INSPECTION PROCEDURE

NOTICE:

After replacing the ECM, the new ECM needs registration and initialization.

HINT:

If DTCs relating to different systems are output, and they share terminal E2 as their ground, check this ground circuit first.

 

1.READ VALUE OF DIESEL TURBO INLET AIR TEMPERATURE SENSOR

1. Connect the intelligent tester to the DLC3.

2. Turn the ignition switch on (IG) and turn the tester ON.

3. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air Temp (Turbo).

4. Read the value.

   Standard value:

   Same value as the actual intake air temperature.

   Result:

   Temperature Displayed	Proceed to
   -40°C (-40°F)	A
   140°C (284°F) or more	B
   OK (same as air temperature near to intake manifold)	C

   HINT:

   1. If there is an open circuit, the tester indicates -40°C (-40°F).
   2. If there is a short circuit, the tester indicates 140°C (284°F) or more.

    

    

 

B	GO TO STEP 4
C	CHECK FOR INTERMITTENT PROBLEMS

A

 

2.CHECK WIRE HARNESS (CHECK FOR OPEN IN WIRE HARNESS)

 

1. Disconnect the A49 diesel turbo IAT sensor connector.

2. Connect terminals 1 and 2 of the diesel turbo IAT sensor wire harness side connector.

3. Connect the intelligent tester to the DLC3.

4. Turn the ignition switch on (IG) and turn the tester ON.

5. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air Temp (Turbo).

6. Read the value.

   Standard value:

   140°C (284°F) or more.

7. Reconnect the diesel turbo IAT sensor connector.

OK	CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE DIESEL TURBO INTAKE AIR TEMPERATURE SENSOR

NG

 

3.CHECK WIRE HARNESS (DIESEL TURBO INLET AIR TEMPERATURE SENSOR - ECM)

 

1. Disconnect the A49 diesel turbo IAT sensor connector.

2. Disconnect the B32 ECM connector.

3. Measure the resistance of the wire harness side connectors.

   Standard resistance:

   Tester Connection	Specified Condition
   A49-2 - B32-113 (THIA)	Below 1 ?
   A49-1 - B32-90 (ETHI)	Below 1 ?

4. Reconnect the diesel turbo IAT sensor.

5. Reconnect the ECM connector.

OK	REPAIR OR REPLACE HARNESS AND CONNECTOR

NG
CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM.

 

4.READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS)

 

1. Disconnect the A49 diesel turbo IAT sensor connector.

2. Connect the intelligent tester to the DLC3.

3. Turn the ignition switch on (IG) and turn the tester ON.

4. Enter the following menus: Powertrain / Engine and ECT / Data List / Intake Air Temp (Turbo).

5. Read the value.

   Standard value:

   -40°C (-40°F) or more.

6. Reconnect the diesel turbo IAT sensor connector.

OK	REPLACE DIESEL TURBO INTAKE AIR TEMPERATURE SENSOR

NG

 

5.CHECK WIRE HARNESS (DIESEL TURBO INLET AIR TEMPERATURE SENSOR - ECM)

 

1. Disconnect the A49 diesel turbo IAT sensor connector.

2. Disconnect the B32 ECM connector.

3. Measure the resistance of the wire harness side connectors.

   Standard resistance:

   Tester Connection	Specified Condition
   A49-2 or B32-113 (THIA) - Body ground	10 K? or higher

4. Reconnect the diesel turbo IAT sensor connector.

5. Reconnect the ECM connector.

OK	REPAIR OR REPLACE HARNESS AND CONNECTOR

NG
REPLACE ECM