as Deano said. shorting somewhere, take a look at the connectors either end (on the motor and on the switch) should be fair accessable, if everything looks ok, attahced and nothing loose then next route is more professional knowledge....

Sounds like it's obviously shorting or something somewhere. Unless you really know what you're doing or can get some better advice, an auto-electrician is what you need.

My friend has just got herself a Mk4 fiesta, 1.25 zetec, (Y reg), and there has been approx 3 old fuses that have been taken out, and when we got it, i put a brand new fuse in with the right amp etc, but its blown again Can anyone help me on this please? Need it doing asap as its for the window wipers!

thank you.