Battery Condition Monitor: Description and Operation
BCM (Battery Condition Monitor) Module
The BCM module determines the battery state of charge, and it controls the battery fan speed by looking at battery voltage, battery input/output current, and battery temperature. The BCM module then sends this information to the MCM to indicate the battery's state of charge and to keep the battery within predetermined limits.
Because battery charging and discharging generates heat in the battery module, the BCM module also controls a fan that keeps the battery module from overheating. The fan operates in one of three modes: off, low, or high.
If the BCM module detects an abnormality, it sends a signal to the MCM, which then turns on the IMA system indicator on the gauge assembly.