Ignition Power Stage: Description and Operation

The ignition module is controlled by the ECM output signal and switches the ignition coil primary circuit. The dwell angle and peak coil current is also controlled by the ignition module. A feature called "stall turnoff" is used to prevent coil overheating and battery discharge if the ignition is left on without the engine running.

NOTE: 1990 model year systems have a four wire (plus ground) ignition module. 1991 ON model year systems have a three-wire (plus ground) ignition module. The modules are interchangeable.

The module is mounted to an aluminum heat sink plate. If the module and heat sink are separated, heat sink compound must be applied between the components upon reassembly.

Ignition Module: