21-028-25 REV. B

Flash: Transmission Control Module (TCM) Updates *Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs):**
• **P0827-00 Up and Down Shift Switch Circuit Low.
• P0826-00 Up and Down Shift Switch Circuit.
• P085F-00 Up and Down Shift Switch Circuit Range/Performance.**
• P1DCD-00 - TCM Monitoring Processor Performance Multiple Clutches Locked Up. Customers may also experience one or more of the following:
• **Vehicle stuck in default gear, and possibly stranded for many minutes.
• Rough/bumpy 2-3 power on upshifts and/or 3-2 coast down shifts.**
• Vehicle enters into limp home mode. **Other software improvements:
• Decreased sensitivity to faults P1D8A and P1D8B.* This bulletin involves inspecting the TCM software level and possibly reprogramming the TCM with the latest available software This bulletin involves inspecting the TCM software level and possibly reprogramming the TCM with the latest available software.