Flash: Transmission Diagnostic And Shift Enhancements
This bulletin involves reprogramming the Transmission Control Module (TCM) with new
software.
A small number of customers may experience a Malfunction Indicator Lamp (MIL)
illumination on vehicles equipped with a 948TE 9 speed automatic transmission (sales
code DFH or DFJ). Upon further investigation, a technician may find Diagnostic Trouble
Code (DTC) P1DAD - Input Shaft-Output Shaft Direction Correlation stored in the TCM
memory.
In addition to addressing the above DTC, this TCM calibration update is being released to
enable the new wiTECH based ?Transmission Quick Learn? procedure to be performed
anytime the transmission adaptation memory cells are cleared or when addressing
customer concerns of poor shift quality. It is also being released to improve transmission
downshift response time during normal driving.
