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IMMOBILISER SYSTEM, Diagnostic DTC:B279A

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DTC Code DTC Name
B279A Theft Deterrent System Communication Line High Fixation
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DESCRIPTION

When the communication line (IMI - EFIO) between the hybrid vehicle control ECU assembly and ID code box (immobiliser code ECU) is stuck high, the hybrid vehicle control ECU assembly stores this DTC.

DTC Code DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B279A The communication line (IMI - EFIO) between the hybrid vehicle control ECU assembly and ID code box (immobiliser code ECU) is stuck high (1 trip detection logic*).

  • Wire harness or connector (disconnection or break in wire harness is main cause)

  • ID code box (immobiliser code ECU)

  • Hybrid vehicle control ECU assembly

 Turn the power switch on (IG) and wait 6 seconds.

Table 1. Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected Fail-safe Operation when Malfunction Detected
Hybrid control system cannot be started Hybrid control system cannot be started
Table 2. Related Data List and Active Test
DTC Code Data List and Active Test
B279A -
Table 3. *a Hybrid Vehicle Control ECU Assembly *b ID Code Box (Immobiliser Code ECU)
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WIRING DIAGRAM

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CAUTION / NOTICE / HINT

Note:

  • When replacing the ID code box (immobiliser code ECU) or hybrid vehicle control ECU assembly, refer to the Service Bulletin.

  • After performing repairs, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.

Tip:

When DTC B279A and the certification ECU (smart key ECU assembly) DTC are output simultaneously, first perform troubleshooting for the certification ECU (smart key ECU assembly) DTC.

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PROCEDURE


  1. Click here

    CLEAR DTC


    1. Clear the DTCs (Click here).


  2. Click here

    CHECK DTC OUTPUT


    1. Turn the power switch on (IG) and wait 10 seconds.

    2. Check for DTCs (Click here).

      Result
      Result Proceed to
      DTC B279A is output A
      DTC B279A and other DTCs are output B
      Tip:

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


  3. Click here

    CHECK CONNECTION OF CONNECTOR


    1. Turn the power switch off.

    2. Check that the connectors are properly connected to the hybrid vehicle control ECU assembly and ID code box (immobiliser code ECU).

      OK
      Connectors are properly connected.

  4. Click here

    CHECK HARNESS AND CONNECTOR (ID CODE BOX (IMMOBILISER CODE ECU) - HYBRID VEHICLE CONTROL ECU ASSEMBLY)


    1. Disconnect the H15 ID code box (immobiliser code ECU) connector.

    2. Disconnect the H212 hybrid vehicle control ECU assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      H15-4 (EFIO) - H212-22 (IMI) Always Below 1 Ω
      H212-22 (IMI) - Body ground Always 10 kΩ or higher

    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      H212-22 (IMI) - Body ground Always Below 1 V

    • OKClick here
    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR

  5. Click here

    REPLACE ID CODE BOX (IMMOBILISER CODE ECU)


    1. Replace the ID code box (immobiliser code ECU) with a new one.

      Tip:

      Refer to the Service Bulletin.


  6. Click here

    REGISTER RECOGNITION CODES


    1. Register the recognition codes in the ECUs.

      Tip:

      Refer to the Service Bulletin.


  7. Click here

    REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID.

      Tip:

      Refer to the Service Bulletin.


  8. Click here

    CLEAR DTC


    1. Clear the DTCs (Click here).


  9. Click here

    CHECK DTC OUTPUT


    1. Check for DTCs (Click here).

      Tip:

      Before checking for DTCs, perform the "DTC Output Confirmation Operation" procedure.

      OK
      DTC B279A is not output.

    • OK

      END (ID CODE BOX (IMMOBILISER CODE ECU) WAS DEFECTIVE)

    • NG

      REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLY (Click here)