Increasing the ampage of a fuse beyond recommended amount is never a good idea. This could cause damage to wires that the fuse is connected to, or even cause fire. The current may be too strong from the foglights. If the fuse is around a 20 amp then going up to a 25 amp would be okay, but I would not go further than 5 extra amps of the recommended.
Tuesday, October 28th, 2008 AT 1:36 AM