Principles of Operation

Starting System

Refer to Wiring Diagram Set 20 for schematic and connector information. Diagrams By Number

Principles of Operation

All vehicles are equipped with a One-Touch Integrated Start (OTIS) starting system.

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

- Correctly coded ignition key, from the Passive Anti-Theft System (PATS)
- Starter motor request, ignition switch in the START position
- Transmission in PARK or NEUTRAL, from the digital Transmission Range (TR) sensor

When the ignition switch is placed in the START position, voltage is supplied to the coil of the starter relay through the OTIS start diode. A starter motor request signal is also sent to the PCM. If the PCM recognizes the needed input signals, it provides the starter relay coil with both voltage and a ground. The starter relay contacts close providing voltage to the starter solenoid, allowing the starter motor to activate. Once the starter motor begins to crank, the ignition switch may be released. The starter motor will continue to crank until the engine starts, the timing circuit in the PCM times out or the ignition switch is turned to the OFF position.


Starting System - Anti-Theft Intervention

The starting system is electronically controlled by the Passive Anti-Theft System (PATS). The PATS recognizes the correct electronically coded ignition key and signals the PCM to provide a ground for the starter relay. The energized relay provides voltage to the starter solenoid, thereby allowing the starter motor to activate.