Dme fault memory entry for the crankshaft sensor

Bulletin number

B120419

Component

Engine and engine cooling

Summary

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.

Owners of these vehicles have filed 168 complaints in the engine category.