My car is a 2008 Volkswagen Beetle (US model). Most of the time, the windshield wipers work just fine, including intermittent mode. However, when turning them on, there is a 20-30% chance that nothing will happen, or that they will start to turn on, but then stop partway. When this happens, turning them off and on won't do anything for a while. At this point, I stop the car, wiggle the wiper blades by hand, and try turning them on again until they work. After a few to several wiggles, they start working again, and continue working until I turn them off. Sometimes, if I wait long enough, they will start working again with no intervention.
I don't think there is a problem with the fuse because like I said, they work normally most of the time (and I checked the fuse and it looks good...even swapped it with a different fuse with the same rating). I suppose there could be a problem with the wiring somewhere, but not sure where to look. It seems like perhaps the wiper motor has a dead spot somewhere, and if the wiper gets caught in this dead zone when they turn off, it won't start again. But during normal operation, momentum carries it past this dead zone, so it's not apparent. This is just a guess. Any ideas?
I took it to the mechanic and told them about the problem, but their "diagnosis" was to turn on the wipers while performing other maintenance, verify that the wipers worked the entire time, and subsequently tell me they could find nothing wrong. At that point, I didn't want to explain how it only fails on startup, because I just wanted my car back.