Theory Of Operation
WARNING: This page is about a different car, the 2013 RAM 1500. However, it is still accessible from the selected car via links, so may be relevant.
The purpose of the diagnostic is to detect an over temperature shutdown of the Transmission Control Module (TCM) to protect the TCM hardware. The TCM has built in temperature sensor circuitry and they are located on the substrate of the TCM, therefore there is no possibility for electrical monitoring (circuit continuity), but out-of-range monitoring (transmitted temperature too low or too high) and a check of all TCM monitoring capabilities.