Alternator & Regulator: Operation

The PCM monitors critical input to control fuel injection, ignition, emission and other engine management functions. The PCM has also been programmed to monitor several charging system related circuits.

• Battery Feed To PCM
• Alternator Field Control
• Battery Charging Voltage (High And Low)

If a problem is sensed in a monitored circuit, a fault code is stored in the PCM's memory and the CHECK ENGINE light will be turned on (with a few exceptions). Fault codes can be read using the CHECK ENGINE light or with the Chrysler Diagnostic Readout Box-II (DRB-II).

For certain fault codes, CHECK ENGINE light will illuminate and PCM will enter limp-in mode. In limp-in mode, PCM attempts to compensate for particular component failure by substituting information from other sources. This allows vehicle operation until proper repairs are made.