Grand Cherokee 2WD V8-5.2L VIN Y (1998)
Voltage Regulator: Description and Operation
SYSTEM OPERATION
The Electronic Voltage Regulator (EVR) is not a separate component. It is actually a voltage regulating circuit located within the Powertrain
Control Module (PCM). The EVR is not serviced separately. If replacement is necessary, the PCM must be replaced.
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 Starting and Charging/Battery/Battery Temperature Sensor for more information). It then compensates and
regulates generator current output accordingly. Also see Starting and Charging/Charging System Operation for additional information.
