Battery Gauge
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, 2012 Chevrolet Suburban, and 2012 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The IPC displays the voltage as determined by the regulated voltage control (RVC). The IPC receives a serial data message from the body control module (BCM) indicating the battery voltage. When the engine is ON, the gauge should be between 10-16 volts. The gauge will default to 0 volts if the IPC detects a loss of communication with the BCM.