Aerostar 2WD V6-245 4.0L (1990)
Ignition Coil: Description and Operation
Coil Pack
The ignition coil pack contains three separate ignition coils, controlled by the EDIS module through three coil leads. Each ignition coil fires two spark
plugs simultaneously; one plug on the compression stroke and one on the exhaust stroke. The spark plug fired on the exhaust stroke uses very little of
the ignition coils stored energy. The Majority of energy is used by spark plug on the compression stroke. Since these two spark plugs are connected in
series, firing voltage of one plug will be negative with respect to ground, while voltage of the other will be positive with respect to ground.
PIN 1 (COIL 1 PRIMARY) IS THE GROUND PATH TO PIN 10 OF THE EDIS MODULE
PIN 2 (COIL 3 PRIMARY) IS THE GROUND PATH TO PIN 11 OF THE EDIS MODULE
PIN 3 (COIL 2 PRIMARY) IS THE GROUND PATH TO PIN 12 OF THE EDIS MODULE
PIN 4 PROVIDES BATTERY VOLTAGE FOR THE COIL PRIMARY CIRCUITS
