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.
The purpose of this 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 Controller Area Network (CAN) bus.