Water-in-Fuel Indicator
WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2005 Ford RV Cutaway, 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Excursion. However, it is still accessible from the selected car via links, so may be relevant.
The water-in-fuel indicator is controlled by the instrument cluster. The cluster receives electronic information from the PCM through the standard corporate protocol (SCP) communication network (Excursion) or the controller area network (CAN) (F-Super Duty or E-Series). If the water-in-fuel sensor indicates that there is water in the fuel separator/housing (located within the fuel condition module), the PCM sends a message to illuminate the water-in-fuel indicator.