21-021-16

Flash: Transmission Shift And Drivability Enhancements This bulletin involves reprogramming the Transmission Control Module (TCM) with the latest available software. A small number of customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs): · **P061B-00 - Internal Control Module Torque Calculation Performance. · P072F-00 - Stuck In Gear 4.** · P0711 - Transmission Fluid Temperature Sensor A Circuit Range-Performance. · P1DAD - Input Shaft-Output Shaft Direction Correlation. · P1CC9 - Unable to Engage Gear. · P1D98 - Incorrect Gear Ratio Clutch B or D Defective. · U1424 - Implausible Engine Torque Signal Received. In addition to correcting the DTCs listed this software update includes the following enhancements: · **Coast down bump on 7-6, 6-5, 5-4, 5-3 downshift improvements. · Cold 1-2, 2-3 upshift improvements. · 1-2, 2-3 upshift flare control improvements. · Power-on upshift improvements. · Lift foot upshift 2-3, 4-5, 8-9 improvements.** · Garage shift improvements (Shifting from Park or Neutral to Drive or Reverse). · 1-2 Shift Quality improvements. · Improved engine performance under certain operating conditions (High Altitude, High Ambient Temperatures and High Humidity). · Hill shift pattern optimization. · Improved redline shift performance. · Improved upshifts, downshifts, coast down shifts and tip shifts.