Sorry if any of these are silly questions...
Can you hear the pump running?
If not there may be a blown fuse.
Do you find water in your boot, running down anywhere? Could be a split pipe.
If the pump appears to be running ok, pull the pipe off at one end and run it... if water comes out then you may have a blocked jet.
Ideally you need to take the pipe off the back of the jet and clean out the jet, but I'm not sure how easy it is to get the jet out of the tailgate, or whether you can access the jet from behind easily or not, as its been a while since I had an escort.
Hope this helps a bit.
Mark L., July 2004