Technical Service Bulletin B120419 — 2020 BMW M850I

DME FAULT MEMORY ENTRY FOR THE CRANKSHAFT SENSOR: This Service Information Bulletin (Revision 1) replaces SI B12 04 19 dated February 2019. Technicians may notice this fault logged during a diagnostic session: Fault code: Control module: Fault Text: 160021 DME Crankshaft sensor: general loss of synchronism Environmental conditions are vehicle speed 0 (stationary) and engine speed less than 1500 rpm. There is no customer-facing symptom nor related check control message displayed. Phantom/pseudo fault due to unsuitable DME software. Background: After parking the vehicle and turning off the engine both DME control units go into sleep mode at different times. The DME of cylinder bank 2 ("secondary") goes into sleep mode first The DME of cylinder bank 1 ("primary") is still awake and can experience a reduction in signal voltage for the crankshaft sensor signal This signal change can mistakenly be evaluated as a skipped crankshaft sensor cog by the DME. If the engine is started while the primary DME is still awake this causes a brief loss of synchronization with the secondary DME. Fault 160021 is logged after three (3) consecutive engine starts with this momentary loss of synchronization. Note: Starting the engine after the primary DME has also gone into sleep mode will avoid the loss of synchronization.