Theory of Operation
WARNING: This page is about a different car, the 2011 RAM Pickup. However, it is still accessible from the selected car via links, so may be relevant.
There are two communication lines between the Powertrain Control Module (PCM) and Generator. Based on sensed battery voltage, the PCM commands the Generator to charge the batteries to a desired voltage. The max voltage the PCM will command the alternator to charge is 14.75 Volts. The PCM then receives feedback from the Generator on the voltage level it is charging the batteries through a sense line. The PCM will not light a MIL lamp for this fault.