Principles of Operation - Key Start

Starting System

Principles of Operation - Key Start

The starting system is electronically controlled by the Passive Anti-Theft System (PATS) feature in the Instrument Cluster (IC). The PATS (Passive Anti-Theft System) recognizes the correct electronically coded ignition key and signals the PCM to provide a ground for the starter relay. The starting system uses a Transmission Range (TR) sensor located in the transmission. The TR (Transmission Range) sensor opens/closes a set of 4 switches that are monitored by the PCM to determine the position of the manual lever (P, R, N, D, L). The TR (Transmission Range) sensor prevents operation of the starter motor unless NEUTRAL or PARK is selected and sends a signal to the PCM to start the vehicle. After the PCM One-Touch Integrated Start (OTIS) feature takes over (this feature assists in starting the engine), the customer is no longer in the loop after the initial crank request, the customer may release the key to the RUN position and the PCM provides voltage to the starter relay. The energized relay provides voltage to the starter solenoid with the key in the START position, thereby allowing the starter motor to activate.