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 monitor the displayed gear position signal in the cluster which is determined using two separate calculations within the Transmission Control Module (TCM). The comparison between the results of the two calculations is evaluated before the displayed gear position is sent to the cluster on the CAN BUS.