Flash: Transmission Diagnostic And Shift Enhancements This bulletin involves reprogramming the...

Bulletin number

21-021-15 REVA

Component

Electrical system

Summary

Flash: Transmission Diagnostic And Shift 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 on vehicles equipped with a 948TE 9 speed automatic transmission (sales code DFH or DFJ). Upon further investigation, a technician may find Diagnostic Trouble Codes (DTCs) stored in the TCM memory. ? P0887 - TCM Power Control Circuit High ? P0711 - Transmission Fluid Temperature Sensor A Circuit Range-Performance ? P1DAD - Input Shaft-Output Shaft Direction Correlation In addition to addressing the above DTCs, 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.

Owners of these vehicles have filed 1,083 complaints in the electrical category.