The electronic control for the ignition system. The module receives a signal from a magnetic pickup or Hall effect sensor in the distributor. The module uses this signal to open and close the ground circuit to the ignition coil to fire the spark plugs. The ignition module itself may be located inside the distributor (GM and some imports), on the distributor housing (some Ford applications) or in the engine compartment. Some modules also control timing advance and retard. If a module goes bad, it usually goes completely dead. The engine won't run because there's no trigger voltage to the ignition coil.

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