Starting System: Description and Operation

Starting System

The starting system consists of the following:

- Starter motor
- Starter motor relay
- Transmission Range (TR) sensor
- Battery
- PCM
- Start diode
- Start/Stop switch
- Remote Function Actuator (RFA) module

When the starter solenoid is energized, a magnetic field is created in the starter solenoid windings. The iron plunger core is drawn into the starter solenoid coil, and a drive lever and pin connected to the starter drive engages the drive pinion gear to the flexplate ring gear. When the plunger is pulled all the way in, its contact disc closes the circuit between the battery and the motor feed terminals. This sends current to the motor, and the drive pinion gear cranks the flexplate to start the engine. When current flows to the starter motor, the starter solenoid pull-in coil is bypassed, and the hold-in coil keeps the drive pinion gear engaged with the flexplate.

An overrunning clutch in the starter drive protects the starter motor from excessive speeds during the brief period before the driver releases the ignition from the START position as the engine starts.

The starting system uses a TR sensor located in the transmission. The TR sensor prevents operation of the starter motor unless NEUTRAL or PARK is selected. The vehicle has One-Touch Integrated Start (OTIS), a computer-assisted cranking system. This feature assists in starting the engine. If the Start/Stop switch is pressed (with brake pedal applied) and released the engine begins cranking, the engine may continue cranking for up to 10 seconds or until the vehicle starts.


One-Touch Integrated Start (OTIS)

Once the ignition is in the START position and the vehicle is in PARK or NEUTRAL, the PCM reads the starter motor request from the RFA module and gains control of the starter engagement. The customer is no longer in the loop after the initial crank request, the customer may release the Start/Stop switch. The PCM will disengage the starter motor based on the following events:

- The engine is started (rpm threshold)
- A set time has been exceeded (calibrated)
- The ignition has been turned to the OFF position


Start/Stop Switch

NOTE: Refer to Description and Operation, Intelligent Access with Push Button Start in Antitheft and Alarm Systems, to review the procedures for achieving the various ignition states (ignition OFF, ignition in ACCESSORY, ignition ON, ignition START) on vehicles with this feature.

The vehicle is equipped with a Start/Stop switch, the vehicle can be started by pressing the Start/Stop switch in combination with the brake pedal rather than using a key. In order to start the vehicle, the passive key must be inside the vehicle. The Start/Stop switch is located on the instrument panel to the right of the steering wheel.