Move the dishwasher away from the wall and out from beneath the kitchen counter, if necessary, being careful not to pull the drain or water-supply pipes.
Unplug the dishwasher and examine the plug. Some models have a rectangular panel on the prong side. If your model does not have this panel, remove the screws on the inside of the plug and remove the back cover. If there is a panel, pry it up with a flathead screwdriver to remove the fuse.
Pull the existing fuse out of its socket and make a note of the marking on the side. Push a replacement fuse with the same amp rating on the side into the socket. Screw the cover back down or push the fuse holder back into its slot.
Plug the dishwasher back in and slide it back into position. The appliance should work correctly. If the fuse repeatedly blows, call an electrician.