DTC B1731: Engine Control Module communication timeout

caution

When the DTC B1731 is set, be sure to diagnose the CAN bus line.
When replacing the ECU, always check that the communication circuit is normal.

DTC SET CONDITION

KOS-ECU checks that the Engine Control Module data has been received via the CAN bus lines, and if not, sets the DTC No. B1731.

TECHNICAL DESCRIPTION (COMMENT)

If no data [ETACS transmits engine random number data to KOS-ECU via the CAN bus lines] is received from the Engine Control Module via the CAN bus lines when the ignition switch is turned to ON position, it is judged as abnormal.

TROUBLESHOOTING HINTS

Malfunction of CAN bus line
Malfunction of KOS-ECU
Malfunction of engine control module
Malfunction of ETACS-ECU
Damaged wiring harness and connectors

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