The Windscreen Wiper Linkage is part of the car electrics system. We have 3 associated problem symptoms connected to it.
The windscreen wipers don't behave correctly, the timing seems to be out of sync and they sometimes don't seem to wipe the screen properly.
The wipers make a loud screeching sound when they're moving. It doesn't sound like it's from the wiper rubbing on the windscreen, it sounds like more of a mechanical screech.
The mechanism that controls the windscreen wipers seems to have corrosion / rust around some of the components.