ECD SYSTEM (w/ EGR Cooler Bypass Valve), Diagnostic DTC:P1496, P1497

DTC Code DTC Name
P1496 Intake Air Temperature Sensor 1 Circuit Low
P1497 Intake Air Temperature Sensor 1 Circuit High

DESCRIPTION

The Diesel turbo inlet air temperature (IAT) sensor senses the IAT after the intake air passes through the intercooler. 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.

A01KI7CE03
DTC No. DTC Detection Condition Trouble Area
P1496

Short in intake air temperature sensor circuit for 0.5 seconds

(sensor resistance value less than 0.0252 kΩ [sensor output voltage less than 0.046 V])

(1 trip detection logic)

  • Open or short in diesel turbo inlet air temperature sensor circuit

  • Diesel turbo inlet air temperature sensor

  • ECM
P1497

Open in intake air temperature sensor circuit for 0.5 seconds

(sensor resistance value more than 156 kΩ [sensor output voltage more than 4.91 V])

(1 trip detection logic)

  • Open or short in diesel turbo inlet air temperature sensor circuit

  • Diesel turbo inlet air temperature sensor

  • ECM

WIRING DIAGRAM

A01KHN6E34

INSPECTION PROCEDURE

Note

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

Tech Tips


  • If different DTCs related to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.

  • Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, and other data from the time the malfunction occurred.

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (INTAKE AIR TEMP [TURBO])


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the tester on.

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

    4. Read values.

      OK
      Same value as the actual intake air temperature
      Result
      Temperature Displayed Proceed to
      -40°C (-40°F) A
      190°C (374°F) or more B
      OK (same as air temperature near to intake manifold) C

      Tech Tips


      • If there is an open circuit, the intelligent tester indicates -40°C (-40°F).

      • If there is a short circuit, the intelligent tester indicates 190°C (374°F) or more.


    B

    READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS) Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS Click here

    A

  2. READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN WIRE HARNESS)


    1. A01KFL2E16
      Text in Illustration
      *1 Diesel Turbo IAT Sensor
      *2 ECM
      *3 Diesel Turbo IAT Sensor
      *a Wire Harness Side

      Disconnect the I5 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 to ON and turn the tester on.

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

    6. Read values.

      Standard
      190°C (374°F)

    OK

    REPLACE DIESEL TURBO INLET AIR TEMPERATURE SENSOR Click here

    NG

  3. READ VALUE USING INTELLIGENT TESTER (CHECK FOR OPEN IN ECM)


    1. A01KF1RE04
      Text in Illustration
      *1 Diesel Turbo IAT Sensor
      *2 ECM
      *3 ECM Connector

      Disconnect the I5 diesel turbo IAT sensor connector.

    2. Connect terminals THIA and E2 of the E12 and E13 ECM connectors.

      Tech Tips

      Before checking, perform a visual and contact pressure check on the ECM connector.

    3. Connect the intelligent tester to the DLC3.

    4. Turn the ignition switch to ON and turn the tester on.

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

    6. Read values.

      Standard
      190°C (374°F)

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    NG

    CONFIRM GOOD CONNECTION AT ECM. IF OK, REPLACE ECM Click here

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


    1. A01KFYJE72
      Text in Illustration
      *1 Diesel Turbo IAT Sensor
      *2 ECM

      Disconnect the I5 diesel turbo IAT sensor connector.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the ignition switch to ON and turn the tester on.

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

    5. Read values.

      Standard
      -40°C (-40°F)

    OK

    REPLACE DIESEL TURBO INLET AIR TEMPERATURE SENSOR Click here

    NG

  5. READ VALUE USING INTELLIGENT TESTER (CHECK FOR SHORT IN ECM)


    1. A01KI6KE04
      Text in Illustration
      *1 Diesel Turbo IAT Sensor
      *2 ECM Connector

      Disconnect the I5 diesel turbo IAT sensor connector.

    2. Disconnect the E12 and E13 ECM connectors.

    3. Connect the intelligent tester to the DLC3.

    4. Turn the ignition switch to ON and turn the tester on.

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

    6. Read values.

      Standard
      -40°C (-40°F)

    OK

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    NG

    REPLACE ECM Click here