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DTC B279A-12: Engine Immobiliser System Circuit Short to Battery [11/2021 - ]: Description

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

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B279A-12 Engine Immobiliser System Circuit Short to Battery The communication line (IMI - EFIO) between the hybrid vehicle control ECU and ID code box (immobiliser code ECU) is stuck high. (1 trip detection logic*)
  • ID code box (immobiliser code ECU)
  • Hybrid vehicle control ECU
  • Wire harness or connector
DTC output confirmation operation:
  1. Turn the ignition switch to ON and wait 6 seconds.
  1. *: Only output while a malfunction is present.
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
RELATED DATA LIST AND ACTIVE TEST

DTC No. Data List and Active Test
B279A-12 -