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Home >> Lexus >> 2010 >> IS 250 RWD, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0010-P015D) >> SFI System >> DTC P0112: Intake Air Temperature Circuit Low Input; DTC P0113: Intake Air Temperature Circuit High Input >> Procedure
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DTC P0112: Intake Air Temperature Circuit Low Input; DTC P0113: Intake Air Temperature Circuit High Input: Procedure

  1. READ VALUE USING INTAKE AIR TEMPERATURE SENSOR (INTAKE AIR) 
    1. Connect Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the tester on.
    4. Enter the following menus: Powertrain / Engine / Data List / All Data / Intake Air.
    5. Read the value displayed on the tester.

      Standard

      Same as actual Intake Air Temperature (IAT).

      Result

      Temperature Displayed Proceed to
      -40 °C (-40°F) A
      140°C (284°F) B
      Same as actual IAT C

      HINT: 

      • If there is an open circuit, Techstream indicates -40°C (-40°F).
      • If there is a short circuit, Techstream indicates 140°C (284°F).

    C → CHECK FOR INTERMITTENT PROBLEMS 

    B → See step   5 

    A: Go to next step 

  2. CHECK INTAKE AIR TEMPERATURE SENSOR (CHECK FOR OPEN IN SENSOR) 
    1. Confirm good connection of the mass air flow meter.
      Fig 1: View Of Intake Air Temperature Sensor Open Circuit Check And Connector Terminals
      GTY139229Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the E29 Mass Air Flow (MAF) meter connector.
    3. Connect terminals THA and E3 of the MAF meter wire harness side connector.
    4. Connect Techstream to the DLC3.
    5. Turn the engine switch on (IG).
    6. Turn the tester on.
    7. Enter the following menus: Powertrain / Engine / Data List / All Data / Intake Air.
    8. Read the value displayed on the tester.

      Standard

      140°C (284°F)

    9. Reconnect the MAF meter connector.

    OK → REPLACE MASS AIR FLOW METER 

    NG: Go to next step 

  3. CHECK ECM (CHECK FOR OPEN IN ECM) 
    1. Confirm good connection of the ECM.
      Fig 2: View Of ECM Open Circuit Check Procedure And Connector Terminals
      GTY145491Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Disconnect the E29 MAF meter connector.
    3. Connect terminals THA and E3 of the E5 ECM connector.

      HINT: 

      Before checking, do visual and contact pressure checks on the ECM connector.

    4. Connect Techstream to the DLC3.
    5. Turn the engine switch on (IG).
    6. Turn the tester on.
    7. Enter the following menus: Powertrain / Engine / Data List / All Data / Intake Air.
    8. Read the value displayed on the tester.

      Standard

      140°C (284°F)

    9. Reconnect the MAF meter connector.

    OK → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    NG → See step   4 

  4. REPLACE ECM. Refer to  REMOVAL 
  5. CHECK INTAKE AIR TEMPERATURE SENSOR (CHECK FOR SHORT IN SENSOR) 
    1. Disconnect the E29 MAF meter connector.
      Fig 3: View Of Intake Air Temperature Sensor Circuit Short Check Procedure
      GTY145041Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Turn the tester on.
    5. Enter the following menus: Powertrain / Engine / Data List / All Data / Intake Air.
    6. Read the value displayed on the tester.

      Standard

      -40°C (-40°F)

    7. Reconnect the MAF meter connector.

    OK → REPLACE MASS AIR FLOW METER 

    NG: Go to next step 

  6. CHECK ECM (CHECK FOR SHORT IN ECM) 
    1. Disconnect the E5 ECM connector.
      Fig 4: View Of ECM Short Check Procedure And Connector Terminals
      GTY145493Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Connect Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Turn the tester on.
    5. Enter the following menus: Powertrain / Engine / Data List / All Data / Intake Air.
    6. Read the value displayed on the tester.

      Standard

      -40°C (-40°F)

    7. Reconnect the ECM connector.

    OK → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    NG → REPLACE ECM. Refer to  REMOVAL