Ignition Control Module: Description and Operation

Ignition Coil/power Transistor Location:

PURPOSE
The power transistor controls ignition discharge by interrupting the ignition coil primary current ground. The power transistor is a solid state component.

LOCATION
Built into the distributor, on the rear of the cylinder head.

OPERATION
The power transistor is a switching device used to interrupt the ignition coil ground connection and induce high voltage from the coil secondary windings. A signal from the ECM controls transistor switching, enabling the ECM to regulate ignition timing based engine operating condition information received from various sensors.