Theory Of Operation
WARNING: This page is about a different car, the 2016 Dodge Durango. However, it is still accessible from the selected car via links, so may be relevant.
This diagnostic monitors for a double failure of the Engine Speed signal received via Controller Area Network (CAN) and an electrical or rationality failure of the Input Speed Sensor. If the Transmission Control Module (TCM) detects a failure with both tests this Diagnostic Trouble Code (DTC) will set.