MARELLI Electronic Ignition System: Description

NOTE: Fiat X1/9 models are equipped with Bosch Electronic Ignition Systems.

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 pick-up 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 the 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 pick-up coil assembly, and provides the coil with proper dwell time and spark timing regardless of engine speed.