Starting System: Notes

WARNING: This page is about a different car, the 2010 Mercury Milan, 2010 Lincoln MKZ, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

The starting system consists of the following components:

Starter motor
Starter motor relay
Transmission Range (TR) sensor - automatic transmission
Clutch cutoff switch - manual transmission
Battery
Ignition switch
PCM
Start diode

When the key is placed in the START position, the starter relay is energized and this sends current to the starter motor, and the drive pinion gear cranks the flexplate/flywheel 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 flywheel until the ignition switch is released from the START position.

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

Vehicles equipped with an automatic transmission have a TR sensor mounted in the transaxle. The TR sensor prevents operation of the starter motor unless NEUTRAL or PARK is selected.

Vehicles equipped with a manual transaxle have a clutch cutoff switch mounted on the clutch pedal bracket. The clutch cutoff switch prevents operation of the starter motor unless the clutch is fully depressed.