MARELLI Electronic Ignition System: Description
The Marelli electronic ignition system consists of an ignition coil, electronic control module, and a breakerless distributor. See Figure.
Marelli distributors are equipped with conventional centrifugal and vacuum advance mechanisms. A 4-tooth trigger (reluctor) is mounted on the distributor shaft and combines with the pickup coil assembly to provide the control module with electrical signals required.
The control module and ignition coil are mounted on a finned, cast aluminum base which not only cools the units, but also provides a system ground. See Figure.
The control module's current limiter provides a constant current flow to the primary circuit, preventing coil damage. The module analyzes the electrical signals from the distributor pickup coil assembly and provides the coil with proper dwell time and spark timing regardless of engine speed.