Dakota Quad Cab 2WD V8-4.7L VIN N (2001)
Water In Fuel Indicator: Description and Operation
The water-in-fuel indicator is located in the Information Center area of the instrument cluster, to the left of center. The water-in-fuel indicator consists of
a stenciled cutout of the words "WATER IN FUEL" in the opaque layer of the instrument cluster overlay. The dark outer layer of the overlay prevents
the indicator from being clearly visible when it is not illuminated. A red lens behind the cutout in the opaque layer of the overlay causes the "WATER IN
FUEL" text to appear in red through the translucent outer layer of the overlay when the indicator is illuminated from behind by a Light Emitting Diode
(LED) soldered onto the instrument cluster electronic circuit board. The water-in-fuel indicator is serviced as a unit with the instrument cluster.
The water-in-fuel indicator gives an indication to the vehicle operator when there is excessive water in the fuel system. This indicator is controlled by a
transistor on the instrument cluster circuit board based upon cluster programming and electronic messages received by the cluster from the Powertrain
Control Module (PCM) over the Programmable Communications Interface PCI data bus. The water-in- fuel indicator Light Emitting Diode (LED)
receives battery current on the instrument cluster electronic circuit board through the fused ignition switch output (run-start) circuit whenever the ignition
switch is in the ON or Start positions; therefore, the LED will always be OFF when the ignition switch is in any position except ON or Start. The LED
only illuminates when it is provided a path to ground by the instrument cluster transistor. The instrument cluster will turn ON the water-in-fuel indicator
for the following reasons:
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Bulb Test - Each time the ignition switch is turned to the ON position the water-in-fuel indicator is illuminated for about two seconds as a bulb
test.
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Water-In-Fuel Lamp-ON Message - Each time the cluster receives a message from the PCM indicating there is excessive water in the fuel
system, the water-in-fuel indicator will be illuminated, and a single chime tone is sounded. The indicator remains illuminated until the cluster
receives a message from the PCM indicating that the water in the fuel system is not excessive, or until the ignition switch is turned to the OFF
position, whichever occurs first. The chime tone feature will only repeat during the same ignition cycle if the water-in-fuel indicator is cycled OFF
and then ON again by the appropriate lamp-OFF and lamp-ON messages from the PCM.
-
Actuator Test - Each time the cluster is put through the actuator test, the indicator will be turned ON, then OFF again during the bulb check
portion of the test to confirm the functionality of the LED and the cluster control circuitry.
The PCM continually monitors the water in the fuel system through the water-in-fuel sensor, then sends the proper messages to the instrument cluster.
For further diagnosis of the water-in-fuel indicator or the instrument cluster circuitry that controls the LED, (Refer to INSTRUMENT CLUSTER -
DIAGNOSIS AND TESTING). For proper diagnosis of the water-in-fuel-sensor, the PCM, the PCI data bus, or the message inputs to the instrument
cluster that control the water-in-fuel indicator, a DRB III scan tool is required. Refer to the appropriate diagnostic information.
