It means a draining of the debris trap under the fuel filter is necessary. Assuming, of course, your Fourtrak retains the original type fuel filter. Look for a large (approx 1 1/2 inch diameter) screw type fitting in the bottom of the fuel filter. There should be a plastic drain pipe leading from this fitting, as well as two wires. If these are not there, then another non genuine type of fuel filter may have been fitted, and the dash light being on may be a result of the incomplete circuit. It may also be how the switch operates in the fitting. Example is the low brake fluid warning switch. This is the float in the brake fluid reservoir. It has a magnet in the middle. When the fluid is low, this magnet contacts and completes the warning circuit in the reservoir. Even filling the reservoir will not extinguish the warning lamp unless the float is dislodged from the bottom of the reservoir. Im not sure, but perhaps the fuel drain switch operates in the same manner. Assuming this is the case, the float may be stuck in the on position, which is probably up, as water being heavier than Diesel, the float would float on water, but not on Diesel.
Hope this helps
Cheers
David
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