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DTC B2271: Ignition Hold Monitor Malfunction (07/2015 -): Procedure

  1. CHECK HARNESS AND CONNECTOR (POWER SOURCE) 
    GTY660281Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A36 certification ECU (smart key ECU assembly) connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A36-2 (+B) - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (to Certification ECU (Smart Key ECU Assembly)

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR IN CIRCUIT CONNECTED TO POWER SOURCE 

    Result:  OK

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (GROUND) 
    GTY667089Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A36-11 (E) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Rear view of wire harness connector
      (Certification ECU (Smart Key ECU Assembly)

    Result:  NG

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  OK

    OK 

    See step  3

  3. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    1. Reconnect the A36 certification ECU (smart key ECU assembly) connector.
      GTY616263Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Certification ECU (Smart Key ECU Assembly)
      - -
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A36-9 (IG2D) - Body ground Engine switch on (ACC) → Engine switch on (IG) 1 V or less → 9 V or higher
      H56-6 (IG1D) - Body ground Engine switch on (ACC) → Engine switch on (IG) 1 V or less → 9 V or higher

    Result:  OK

    OK 

    USE SIMULATION METHOD TO CHECK 

    (Refer to HOW TO PROCEED WITH TROUBLESHOOTING (07/2015 -) )

    Result:  NG

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

    (Refer to REMOVAL (07/2015 -) )