Theory Of Operation

The Transmission Control Module (TCM) is programmed during manufacturing with generic software to facilitate testing. This software does not have the proper calibrations to control a transmission in a vehicle. The check for generic software is made at power-up. If generic software is detected by the controller the Malfunction Indicator Lamp (MIL) will illuminate immediately and will stay illuminated until the proper software is installed.

This Diagnostic Trouble Code (DTC) will cause the Transmission to be placed into Limp-in mode.