Notso: Arcing begins with pinprick flashes around the bus bar. It isn't dramatic, but it should be noticeable and if reported in the early stages the window can be replaced before it is in danger of cracking. The maintenance schedule calls for inspection of the windows for signs of arcing and, yes, maintenance do find such signs. Often. It is a fact that most windscreen replacements are for delamination and/or evidence of arcing discovered during such maintenance checks.