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Principles of Operation




Starting System

Principles of Operation

NOTE: This vehicle may be equipped with Passive Anti-Theft System (PATS) that disables the engine from starting 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 Instrument Cluster (IC). If there is a PATS (Passive Anti-Theft System) concern that caused the engine not to start, the anti-theft light flashes rapidly or glows steadily in the IC (Instrument Cluster). to diagnose a PATS (Passive Anti-Theft System) concern.

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

- PATS (Passive Anti-Theft System) enable status from the IC (Instrument Cluster), (if equipped with PATS (Passive Anti-Theft System))

- Transaxle in PARK or NEUTRAL from the Transmission Range (TR) sensor

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

When the ignition switch is turned to START, the PCM receives a request to crank and start the engine. If the PCM recognizes the correct input signals and the gear selector is in the NEUTRAL or PARK position, the PCM provides a ground to the starter relay coil. The starter relay contacts close, providing voltage to the starter solenoid, allowing the starter motor to activate.