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RecallGazette

Vehicle problems, recalls & safety intelligence

BMW 320I 2017–2024technical service bulletin

Bulletin B120721 · NHTSA communication 10245367 · issued Nov 9, 2023

Technical service bulletin
communication type
Engine and Engine Cooling
component
2017–2024
model years
60
vehicle entries

Official summary

Check Control message (CCM) indicates: (ID 213): Stop, exercising due care. Voltage supply The Service Engine Soon light is on with the following DME Fault Code: 21B209 - Starter alternator / belt for 48V system (OSA_RIEMEN_RISS): Belt betweenCombustion engine and starter generator torn And/or one or more of the following other issues are also occurring: Noise in the area of the belt drive. Odor from the engine compartment. Smoke formation in the area of the belt drive. Drive belt damaged or prematurely worn. Torn drive belt.

What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.