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Ignition Control Module: Description and Operation

Ignition Coil And Distributor Location:




Ignition Coil And Driver:




Ignition Circuit:





The ignition coil and module are mounted on the front of the right cylinder head. The module receives ignition timing signals from the ECM over the EST signal line. When the voltage on the EST line is in the "High" state (approx. 4.5 volts) the module grounds the ignition coil primary circuit, creating a magnetic field around the coil secondary windings. When the EST voltage goes "Low", the module opens the primary circuit, causing the magnetic field to collapse suddenly and induce high voltage in the secondary windings. This high voltage is directed to the distributor through the coil wire and the distributor directs the spark voltage to the correct spark plug through the secondary wires (spark plug wires).