Theory Of Operation
WARNING: This page is about a different car, the 2013 Fiat 500c and 2013 Fiat 500. However, it is still accessible from the selected car via links, so may be relevant.
The Transmission Control Module (TCM) performs basic system checks to ensure proper controller operation. This Diagnostic Trouble Code (DTC) sets when the TCM cannot correctly write to, or read from the RAM.