i had the same problem with my punto and it turned out to be water getting into the wiper motor causing it to seize.easy to replace but i managed to unseize mine and just had to replace the bearing now all seem's to be ok.
neil
May 2010
Hi,
Start with the fuse, if this is intact put a meter across the connections to the motor and see if you get voltage when you select wipe. If you have voltage but the motor won't run, then you probably have a duff motor.
Cheers now