Click here

ENTRY AND START SYSTEM(for Start Function), Diagnostic DTC:B279A12

Click here
Click here
DTC Code DTC Name
B279A12 Engine Immobiliser System Circuit Short to Battery
Click here

DESCRIPTION

If 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 will store this DTC.

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B279A12 Engine Immobiliser System Circuit Short to Battery 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*).

  • Harness or connector

  • ID code box (immobiliser code ECU)

  • Hybrid vehicle control ECU assembly

DTC output confirmation operation:


  • 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 No. Data List and Active Test
B279A12 -
Table 3. *a ID Code Box (Immobiliser Code ECU) *b Hybrid Vehicle Control ECU Assembly
Click here

WIRING DIAGRAM

Click here

CAUTION / NOTICE / HINT

Note:

  • When using the GTS with the power switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start. While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.

  • Click here

    The entry and start system (for Start Function) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the entry and start system (for Start Function) after confirming that the communication systems are functioning properly.

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

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

Tip:

When DTC B279A12 and a certification ECU (smart key ECU assembly) DTC are output simultaneously, first perform troubleshooting for the certification ECU (smart key ECU assembly) DTC.

Click here

PROCEDURE


  1. 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.
      Result
      Result Proceed to
      The connectors are properly connected A
      The connectors are not properly connected B

  2. Click here

    CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (TERMINAL IMI)


    1. B004XZQC24
      *a

      Component with harness connected

      (Hybrid Vehicle Control ECU Assembly)

      		 *b Waveform
      *c Approximately 160 ms. *d Approximately 270 ms.

      Using an oscilloscope, check the waveform.

      Measurement Condition
      Tester Connection Condition Tool Setting Specified Condition
      G92-11 (IMI) - Body ground Within 3 seconds of hybrid control system start or within 3 seconds of power switch turned on (IG) after cable disconnected and reconnected to auxiliary battery 2 V/DIV., 500 ms./DIV.

      Pulse generation

      (See waveform)
      Result
      Result Proceed to
      11 to 14 V A
      Below 1 V B
      Normal wavform

  3. Click here

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


    1. Disconnect the G92 hybrid vehicle control ECU assembly connector.

    2. Disconnect the G58 ID code box (immobiliser code ECU) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G58-4 (EFIO) - G92-11 (IMI) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    • OK

      REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR