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One-Touch Start System (OSS)




DTC B1731 ECM authenticate time-out

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.

DIAGNOSTIC FUNCTION

If the necessary data cannot be received from ECM via CAN bus line during the engine starting certification with ECM, OSS-ECU determines that a problem has occurred, and sets the DTC B1731. At the same time, OSS-ECU displays the immobilizer certification system inspection warning screen to the multi information display of the combination meter.

DTC SET CONDITION

Check Conditions

- At engine starting certification
Judgment Criterion

- At the engine starting certification with ECM, necessary data cannot be received from ECM via CAN bus line.

TROUBLESHOOTING HINTS

- Malfunction of the CAN bus line
- Malfunction of ECM
- Malfunction of OSS-ECU

DIAGNOSIS

1. Using scan tool MB991958, diagnose the CAN bus line.
2. ECM DTC check
3. OSS-ECU DTC recheck