LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Ford >> 2012 >> Fusion FWD L4-2.5L >> Repair and Diagnosis >> Powertrain Management >> Ignition System >> Description and Operation >> Engine Ignition
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Engine Ignition




Engine Ignition

The Electronic Ignition (EI) system is a coil-on-plug ignition system. The coil-on-plug ignition system consists of the:

- ignition coil-on-plugs.

- spark plugs.

- Crankshaft Position (CKP) sensor.

- Camshaft Position (CMP) sensor.

The ignition coil-on-plugs:

- change low voltage signals from the PCM to high voltage pulses.

- supply the high voltage pulses to the spark plugs.

- are connected directly to each spark plug.

- have replaceable coil boots.

The spark plugs:

- change high voltage pulses into a spark which ignites the fuel and air mixture.

The CKP (Crankshaft Position) sensor:

- is a variable reluctance sensor.

- is triggered by a 36-minus-1 tooth trigger wheel mounted on the crankshaft.

- provides base timing and crankshaft speed (rpm) to the PCM.

- is essential for calculating spark timing.

The CMP (Camshaft Position) sensor:

- is a Hall-effect sensor.

- provides camshaft rotational location information to the PCM.

- sends the PCM a signal indicating camshaft position used for fuel synchronization.