From VIN S5220000

With the ignition switch in the ON or START position, battery voltage is applied to the ignition coil in the distributor assembly. As the distributor shaft turns, the engine or powertrain control module receives crankshaft position sensor inputs from the distributor. Based on these inputs and other engine sensors, the Engine Control Module (ECM/PCM) sends a signal to the ignition control module. The module grounds the primary winding of the ignition coil. When the current flow through the primary winding is stopped, a high voltage current is induced in the secondary winding of the ignition coil; the high voltage current flows through the distributor cap and rotor to the proper spark plug.

A signal is also sent from the ignition coil to the instrument cluster to operate the tachometer.