IMMOBILISER SYSTEM, Diagnostic DTC:B279986

DTC Code DTC Name
B279986 Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid

DESCRIPTION

If there is a communication malfunction between the hybrid vehicle control ECU and ID code box (immobiliser code ECU), or when the communication ID codes do not match, the hybrid vehicle control ECU stores this DTC.

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B279986 Engine Immobiliser System Signal (Some Circuit Quantity, Reported via Serial Data) Invalid

Either of the following conditions is met (1 trip detection logic*):


  • A malfunction is detected in the communication or communication lines between the hybrid vehicle control ECU and ID code box (immobiliser code ECU).

  • The communication ID codes of the hybrid vehicle control ECU and ID code box (immobiliser code ECU) do not match.


  • ID code box (immobiliser code ECU)

  • hybrid vehicle control ECU

  • Wire harness or connector

DTC output confirmation operation (Perform either of the following):


  • Start the hybrid system and wait for 10 seconds. If there is a malfunction, the hybrid control system will stop (communication begins within 3 seconds of the hybrid control system start, and DTCs are stored after 6 seconds).

  • Connect the cable to the negative (-) auxiliary battery terminal, start the hybrid system and wait for 10 seconds (communication begins within 3 seconds of the power switch being turned on (IG), and DTCs are stored after 6 seconds).


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 -
Related Data List and Active Test
DTC No. Data List and Active Test
B279986 -

WIRING DIAGRAM

A003NTQE19
*a ID Code Box (Immobiliser Code ECU)
*b Hybrid Vehicle Control ECU

CAUTION / NOTICE / HINT

Note


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

  • After performing repairs, confirm that no DTCs are output by performing "DTC Output Confirmation Operation."

Tech Tips

When DTC B279986 and a certification ECU (smart key ECU assembly) DTC are output simultaneously, first perform troubleshooting for the certification ECU (smart key ECU assembly) DTC.

PROCEDURE


  1. REGISTER ECU COMMUNICATION ID


    1. Register the communication ID codes.

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT
  2. CHECK HYBRID VEHICLE CONTROL ECU (TERMINAL IMO)


    1. Using an oscilloscope, check the waveform.

      A003M99C10
      *a

      Component with harness connected

      (Hybrid Vehicle Control ECU)

      *b Waveform
      *c Approximately 160 ms. *d Approximately 270 ms.
      Measurement Condition
      Tester Connection Condition Tool Setting Specified Condition
      I3-23 (IMO) - Body ground Turn the power switch on (READY) 2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform)

      Result
      Result Proceed to
      Normal waveform A
      Terminal IMO stuck low (2.4 V or less) B
      Waveform not output, or has abnormal wavelength or shape C

    B
    C
    A
  3. CHECK HYBRID VEHICLE CONTROL ECU (TERMINAL IMI)


    1. Using an oscilloscope, check the waveform.

      A003KZ4C09
      *a

      Component with harness connected

      (Hybrid Vehicle Control ECU)

      *b Waveform
      *c Approximately 160 ms. *d Approximately 270 ms.
      Measurement Condition
      Tester Connection Condition Tool Setting Specified Condition
      I3-10 (IMI) - Body ground Power switch turned on (IG) using registered electrical key transmitter sub-assembly 2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform)

      Result
      Proceed to
      OK
      NG

    NG
    OK
  4. REGISTER ECU COMMUNICATION ID


    1. Register the ECU communication ID codes.

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT
  5. CHECK WHETHER HYBRID CONTROL SYSTEM STARTS


    1. Using an electrical key transmitter sub-assembly which is registered to the vehicle, turn the power switch on (IG).

    2. Check that the hybrid control system starts 5 seconds after the power switch turned on (IG).

      OK
      Hybrid control system starts normally.
      Result
      Proceed to
      OK
      NG

    OK
    NG
  6. CHECK ID CODE BOX (IMMOBILISER CODE ECU)


    1. Disconnect the I3 hybrid vehicle control ECU connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      I3-23 (IMO) - Body ground Power switch turned on (IG) using registered electrical key transmitter sub-assembly Terminal IMO stuck low (2.4 V or less)
      Terminal IMO stuck high (12 V) or abnormal waveform
      Result
      Result Proceed to
      Terminal IMO stuck low (2.4 V or less) A
      Terminal IMO stuck high (12 V) or abnormal waveform B

    B
    A
  7. CHECK HARNESS AND CONNECTOR (ID CODE BOX (IMMOBILISER CODE ECU) - HYBRID VEHICLE CONTROL ECU)


    1. Disconnect the I20 ID code box (immobiliser code ECU) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I20-3 (EFII) - I3-23 (IMO) Always Below 1 Ω
      I20-3 (EFII) or I3-23 (IMO) - Body ground Always 10 kΩ or higher
      I20-4 (EFIO) - I3-10 (IMI) Always Below 1 Ω
      I20-4 (EFIO) or I3-10 (IMI) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG
    OK
  8. REPLACE ID CODE BOX (IMMOBILISER CODE ECU)


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

      Tech Tips

      Refer to Service Bulletin.

      Result
      Proceed to
      NEXT

    NEXT
  9. CLEAR DTC


    1. Clear the DTCs.

      Click here


      Powertrain > Hybrid Control > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT
  10. CHECK FOR DTC


    1. Check for DTCs.


      Powertrain > Hybrid Control > Trouble Codes

      Tech Tips

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

      OK
      DTC B279986 is not output.
      Result
      Proceed to
      OK
      NG

    OK
    NG