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Inspection Procedure: Procedure

WARNING: This page is about a different car, the 2011 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK DTC OUTPUT 
    1. Recheck for DTCs. Refer to DTC CHECK / CLEAR .

      HINT: 

      If any DTCs other than DTC B279A are output, troubleshoot those DTCs first.

      Result

      Result Proceed to
      DTC B279A and other DTCs reoutput A
      DTC B279A reoutput B

    A → See step   8 

    B: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (TRANSPONDER KEY ECU - ECM) 
    1. Disconnect the transponder key ECU assembly connector.
    2. Disconnect the ECM connector.
      Fig 1: Transponder Key ECU Assembly And ECM Connector Terminal Identification
      GTY175222Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance and voltage according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      E21-13 (EFIO) - A50-11 (IMI) Always Below 1 Ω
      E21-13 (EFIO) - Body ground Always 10 kΩ or higher

      Standard Voltage

      Tester Connection Condition Specified Condition
      E21-13 (EFIO) - Body ground Always Below 1 V

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. CHECK ECM (INPUT) 
    1. Reconnect the transponder key ECU assembly connector.
    2. Reconnect the ECM connector.
    3. Measure the waveform.
      Fig 2: ECM Connector Terminal Identification
      GTY292362Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Waveform 1 (Reference)

      Item Content
      Terminal No. (Symbols) A50-11 (IMI) - B31-104 (E1)*1
      A50-11 (IMI) - B31-105 (E1)*2
      Tool Setting 2 V/DIV., 1 s./DIV.
      Condition Ignition switch ON
      • *1: for 2AZ-FE
      • *2: for 2ZR-FE

      Result

      Result Proceed to
      OK (for 2ZR-FE) A
      OK (for 2AZ-FE) B
      NG C

    B → See step   9 

    A → See step   10 

    C: Go to next step 

  4. REPLACE TRANSPONDER KEY ECU ASSEMBLY 
    1. Replace the transponder key ECU assembly. Refer to REMOVAL .

    NEXT: Go to next step 

  5. REGISTER KEY 
    1. Register the key. Refer to REGISTRATION .

    NEXT: Go to next step 

  6. REGISTER ECU COMMUNICATION ID 
    1. Register the ECU communication ID. Refer to REGISTRATION .

    NEXT: Go to next step 

  7. CHECK DTC OUTPUT 
    1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    2. Recheck for DTCs.

      OK

      B279A is not reoutput.

      Result

      Result Proceed to
      NG (for 2ZR-FE) A
      NG (for 2ZA-FE) B
      OK C

    B → See step   9 

    A → See step   10 

    C → END (TRANSPONDER KEY ECU IS DEFECTIVE) 

  8. GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART 
  9. REPLACE ECM. Refer to  REMOVAL 
  10. REPLACE ECM. Refer to  REMOVAL 
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