Theory Of Operation
WARNING: This page is about a different car, the 2013 RAM 3500 HD and 2013 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
The Intelligent Battery Sensor (IBS) is mounted in-line with the negative Battery Cable. The IBS monitors the Battery state of charge and current draw. The IBS also has a built in thermistor that calculates the Battery temperature. This information is reported through a LIN BUS circuit to the Body Control Module (BCM). The BCM broadcasts the information to the Powertrain Control Module (PCM) over the CAN BUS.