RAE Distributor The ignition distributor is at the heart of the engines ignition system. Its 3 basic functions are to trigger the firing of the ignition coil, to control timing advance, and to distribute the coils high voltage output to the individual spark plug.

On older applications with breaker point ignition systems, the contact points switch the ignition coil's primary voltage on and off. The points are mounted on a movable plate in the distributor housing. Cam lobes on the distributor shaft rotate against a plastic block on the points to open and close the points. On newer applications with electronic ignition, the distributor can contain an inductive pickup, an optical sensor or even a hall affect switch instead of points to generate a signal for the ignition module, which in turn switches the coil on and off. On many applications, the ignition module itself can also be located inside the distributor or mounted on the distributor housing.