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B1401

DTC B1401 (1-1): OnStar Control Unit Internal Error (CPU Error)

1. Delete the DTCs.
2. Turn the ignition switch OFF, and then back ON (II).
3. Check for DTCs.

Is DTC B1401 (1-1) indicated?

YES - Replace the OnStar control unit.

NO - Intermittent failure. The system is OK at this time. Check for loose or poor connections.