Theory Of Operation
WARNING: This page is about a different car, the 2005 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
The Transmission Control Module (TCM) performs various internal tests to verify proper controller operation. This DTC indicates that watch dog circuitry external to the microprocessor has detected an error. If the TCM watch dog circuitry external to the microprocessor detects an error, the controller will enter Limp-in mode and illuminate the MIL.