Circuit Operation - Charging System

The Generator provides voltage to operate the car's electrical system and to charge it's battery. A magnetic field is created when current flows through the Rotor. This field rotates as the rotor is driven by the engine, creating an AC voltage in the Stator Windings. The AC voltage is converted to DC voltage by the Rectifier Bridge, and is supplied to the electrical system at the battery terminal.

The Generator's Regulator uses digital techniques to supply the Rotor current and thereby control the output voltage. The Rotor current is proportional to the width of the electrical pulse supplied by the Regulator. When the Ignition Switch is placed in the "RUN" position, voltage is supplied to terminal "L," turning on the Regulator. Narrow width pulses are supplied to the Rotor creating a weak magnetic field. When the engine is stared, the Regulator senses Generator rotation by detecting AC voltage at the stator through an internal wire. Once the engine is miming, the Regulator varies the field current by controlling the pulse width. This regulates the Generator output voltage for proper Battery charging and electrical system operation. The Regulator sends output to the PCM which lights the Volts telltale if a fault is detected.