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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 key is used or an invalid PCM ID is received. PATS is controlled by the Instrument Cluster (IC). If there is a PATS concern that caused the engine not to start, the anti-theft light flashes rapidly or glows steadily in the IC. Refer to Anti-Theft - Passive Anti-Theft System (PATS) Testing and Inspection to diagnose a PATS concern.

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

- PATS enable status from the IC, (if equipped with PATS)
- 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.