RAM 2500 Truck 4WD L6-5.9L DSL Turbo VIN 6 (1999)
Water In Fuel Sensor: Description and Operation
WATER-IN-FUEL (WIF) SENSOR-ECM INPUT
The sensor sends an input to the Engine Control Module (ECM) when it senses water in the fuel filter water separator. As the water level in the
filter/separator increases, the resistance across the WIF sensor decreases. This decrease in resistance is sent as a signal to the ECM and compared
to a high water standard value. Once the value reaches 30 to 40 kilohms, the ECM will activate the water-in-fuel warning lamp through CCD bus
circuits. This all takes place when the ignition key is initially put in the ON position. The ECM continues to monitor the input at the end of the
intake manifold air heater post-heat cycle.
Water-In-Fuel Sensor Location
The WIF sensor is located at the bottom of the fuel filter/water separator canister.
