General

The charging system consists of a generator which generates current to supply the vehicle electrical system and maintain the battery in a charged condition.

The generator is driven by the accessory drive belt. For additional information, refer to Drive Belts, Mounts, Brackets and Accessories. When the engine is started, the generator begins to generate Alternating Current (AC) which is converted to Direct Current (DC) internally. The DC current is controlled by the voltage regulator (located on the back of the generator), and then supplied to the battery.

The charging system voltage is controlled by the Powertrain Control Module (PCM). The generator charges the battery and at the same time it supplies all the electrical loads that are required. The battery is more effectively charged with a higher voltage when the battery is cold and a lower voltage when the battery is warm. The PCM is able to adjust the charging voltage according to battery temperature by using a signal from the Intake Air Temperature (IAT) sensor. This means that the voltage setpoint is calculated by the PCM and communicated to the regulator by a communication link.

The PCM simultaneously controls and monitors the output of the generator. When the current consumption is high or the battery is discharged the system is able to increase the idle speed.

To minimize the engine drag when starting the engine, the PCM controls the generator. The generator does not produce any output until the engine has started. The PCM then progressively increases the output of the generator.

The PCM controls the operation of the charging system warning indicator in the instrument cluster. The PCM is therefore responsible for turning the warning indicator off after the engine is started and illuminating it under fault conditions (when the generator is not generating the correct amount of current with the engine running). The warning indicator will also be illuminated by the PCM at key - on engine off and stall conditions.

Units should be repaired as an assembly and not dismantled for repair. For additional information, refer to Alternator.