21-027-20

Flash: Transmission Control Module (TCM) Updates This bulletin involves reprogramming the TCM with the latest available software. Some customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation, a technician may find one or more of the following Diagnostic Trouble Codes (DTCs) have been set: P0780 - Gear Shift Malfunction. P1DD2-00 - Torque Request Signal From TCM Denied. Customers or technicians may experience the following: Transmission will be placed into Limp-in mode. While driving at 65 kph (40 mph) a bump will be felt and the RPM will jump to 4000 RPM.