Flash: Powertrain Diagnostic and System Improvements

Bulletin number

18-099-15

Component

Electrical system

Summary

Flash: Powertrain Diagnostic and System Improvements This bulletin involves selectively erasing and reprogramming the Powertrain Control Module (PCM) with new 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) set in the PCM: ? U0140 - Lost Communication With Body Control Module (BCM) (RT Vehicles Only). ? P0456 - Evap System Small Leak. Transmission Enhancements are also included with this software release. These changes include the following: ? Garage shift engagements into D may be harsh at times after shutdowns of 10-30 minute duration. ? 5/6 Upshift timing adjusted to improve top speed performance (markets where speeds in excess of 161 kph (100 mph) are permitted). NOTE: The Transmission Enhancements only apply to vehicles equipped with the 3.6L engine (sales code ERB).

Owners of these vehicles have filed 824 complaints in the electrical category.