Flash: Transmission Control Module (TCM) Updates Customers may experience one or more of the following: ●...

Bulletin number

21-049-26

Component

Power train

Summary

Flash: Transmission Control Module (TCM) Updates Customers may experience one or more of the following: ● Intermittently during low‑speed parking maneuvers when the driver moves from Drive (D) to Reverse (R) at the exact moment the Engine Stop/Start (ESS) system shuts the engine off. ● When the timing aligns, the engine will not automatically restart, and the Instrument Panel Cluster (IPC) displays a shift to park to start reated message. ● NOTE: The behavior results from safety logic that prevents the PCM from restarting the engine while the transmission is in an engaged gear. NOTE: No Diagnostic Trouble Codes (DTCs) or Malfunction Indicator Lamp (MIL) are set because the system is functioning as designed. NOTE: This may appear as an ESS stall, but it is actually a controlled inhibit, not a malfunction. NOTE: The condition is difficult to reproduce due to the timing window required. This bulletin involves inspecting and possibly reprogramming the PCM and Transmission Control Module (TCM) with the latest available software.

Owners of these vehicles have filed 20 complaints in the transmission category.