to be no reason for it. One day they work fine, the next day they are going mad and refuse to stop. What's the
reason for this? Unfortunately it's not as simple as pointing out 1 issue. Over the years I have seen and heard
about every part of the wiper system causing the wipers to stay on, or the less likely "won't work at all".

The problems can normally be narrowed down to the following:
Wiper motor
Wiper relay
Wiper stalk
SAM unit
Auto wiper sensor
In my experience, that list is in order of likeliness and most of these faults are caused by water.
It's no secret that the wiper motor allows water inside the motor housing, it is covered here.
