Water in Fuel Indicator (Diesel Only)
WARNING: This page is about a different car, the 2004 Ford RV Cutaway, 2004 Ford Econoline, 2004 Ford E450 Super Duty, and 2004 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
The water in fuel indicator receives a ground signal when water is sensed in the fuel. The PCM provides the ground for the water in fuel warning indicator. The water in fuel indicator prove-out is in the RUN position and is controlled by the PCM.