Fuse for wiper keeps blowing out
 

I have a 2000 C280 with 80k miles on it - runs great and the wiper system runs great BUT every 1-2 hrs of use of the wiper blade the fuse goes out and it stops working - i replace the #44 fuse in the fuse box with a 40A fuse as recommended and it does it again

I cant figure our who to take the car to and what is really wrong - or where is the probable problem

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