Charging System Warning Indicator
WARNING: This page is about a different car, the 2009 Mercury Grand Marquis and 2009 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.
The instrument cluster (IC) receives the charging system status from the PCM over the HS-CAN. Charging system data is monitored by the instrument cluster (IC) and when the charging system voltage is low, illuminates the charging system warning indicator.