Depends on the make model of cars. But generally its under the dash board. Either under the steering column or on the left side panel where the door hinge side you will see a panel look under the dash. I think the fuse is a 10 amp red
On 91-94 Marquis, Crown Vic, Town Car, the wiper "fuse" is a small aluminum plug-in box on the fuse board that has 8.25 stamped on it. It is an 8.25 amp circuit breaker. Not a fuse. On the board there is also a 20 amp circuit breaker, and the rest should be various colored spade fuses. The wiper C.B. is the larger one of the aluminum boxes, approximately 5/16 thick by about 1" x 3/4". It is in the #2 position on the board. (Position 3 is blank, and is covered by the CB width.)
Number 2 is the 8.25 amp circuit breaker. This is most likely used on many other Fords beside the ones I listed.
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