Ignition System - NIPPONDENSO Electronic: Description
Nippondenso electronic ignition system includes a breakerless distributor, an ignitor (ignition control unit or module), a special ignition coil and ignition switch. Distributor consists of a housing, rotor and cap. It contains a signal rotor (timing rotor or reluctor), a magnet and a magnetic pick-up coil assembly. See Fig 1.
On Toyota Camry, Corolla and Tercel models, ignitor and ignition coil are inside distributor. On other models, transistorized ignitor is mounted on ignition coil housing.
Toyota Cressida and Supra models use Electronic Spark Advance (ESA). Both systems use a computer to control spark advance. All other distributor models contain conventional centrifugal and vacuum advance mechanisms.