Without Intelligent Access (IA)

Starting System

Principles of Operation - Without Intelligent Access (IA)

NOTE: This vehicle is equipped with Passive Anti-Theft System (PATS) that disables the engine if an unprogrammed PATS (Passive Anti-Theft System) key is used or an invalid PCM ID is received. PATS (Passive Anti-Theft System) is controlled by the Body Control Module (BCM). If the PATS (Passive Anti-Theft System) disables the engine from starting, the Instrument Panel Cluster (IPC) displays "STARTING SYSTEM FAULT" in the message center. Refer to Antitheft and Alarm Systems to diagnose a PATS (Passive Anti-Theft System) concern.

The starting system is electronically controlled by the PCM. The PCM receives the following inputs:

- Request to start the engine, ignition switch in the START position

- PATS (Passive Anti-Theft System) enable status

- Correct transmission PARK or NEUTRAL input from the Transmission Range (TR) sensor

When the PCM receives the correct inputs, voltage and ground is supplied to the starter relay coil. The starter relay coil is energized causing the relay contacts to close providing voltage to the starter solenoid, allowing the starter motor to crank and start the engine. The PCM disengages the starter once an engine rpm threshold is reached, a set crank time is exceeded or the ignition is turned OFF.