Engine Controls - Theory & Operation: Alternator

Chrysler Motors passenger cars use either a Nippondenso or a Bosch alternator. The 3.0L and 3.3L engine use Nippondenso alternators. The 2.2L and 2.5L engines may be equipped with either a Bosch or Nippondenso unit.

The alternator consists of a rotor, stator, rectifiers, front and rear covers and drive pulley. On all vehicles, voltage regulation is controlled by the Single Board Engine Controller (SBEC).

Alternator diodes convert AC current to DC current. The engine controller monitors critical input and output of the charging system, making sure it is working properly.

The engine controller will store in memory any failures within the monitored circuits. Engine controller will translate a failure in the form of fault codes when on-board diagnostics are entered.

The system's self-diagnostic abilities, if properly used, can simplify testing. The engine controller is programmed to monitor several different engine control system circuits. If a problem is sensed with a monitored circuit, a fault code is stored in the engine controller's memory. The check engine light will illuminate and engine controller may enter limp-in mode, if necessary. In this mode, engine controller attempts to compensate for the component or circuit by substituting information from other sources. This allows vehicle to operate until proper repairs are made.