The charging system is turned on and off with the ignition switch. When the ignition switch is turned to the ON position, battery Voltage is applied to the generator rotor through one of the two field terminals to produce a magnetic field. The generator is driven by the engine through a serpentine belt and pulley arrangement. The amount of DC current produced by the generator is controlled by the EVR (field control) circuitry, contained within the PCM. This circuitry is connected in series with the second rotor field terminal and ground. All vehicles are equipped with On-Board Diagnostics (OBD) . All OBD-sensed systems, including the EVR (field control) circuitry, are monitored by the PCM. Each monitored circuit is assigned a Diagnostic Trouble Code (DTC) . The PCM will store a DTC in electronic memory for any failure it detects. See On-Board Diagnostic System Test for more information. Generator The generator is belt-driven by the engine. It is serviced only as a complete assembly. If the generator fails for any reason, the entire assembly must be replaced. As the energized rotor begins to rotate within the generator, the spinning magnetic field induces a current into the windings of the stator coil. Once the generator begins producing sufficient current, it also provides the current needed to energize the rotor. The Y type stator winding connections deliver the induced AC current to 3 positive and 3 negative diodes for rectification. From the diodes, rectified DC current is delivered to the vehicle electrical system through the generator, battery, and ground terminals. Noise emitting from the generator may be caused by:
Battery Temperature Sensor The battery temperature sensor is used to determine the battery temperature. This temperature data, along with data from monitored line Voltage, is used by the PCM to vary the battery charging rate. System Voltage will be higher at colder temperatures and is gradually reduced at warmer temperatures.
Operation: The amount of DC current produced by the generator is controlled by EVR circuitry contained within the PCM. This circuitry is connected in series with the generators second rotor field terminal and its ground. Voltage is regulated by cycling the ground path to control the strength of the rotor magnetic field. The EVR circuitry monitors system line Voltage and battery temperature (refer to Battery Temperature Sensor for more information). It then compensates and regulates generator current output accordingly.