Windshield Wiper/washer Linkages problems of the 1998 Chevrolet C/k Pickups

1 windshield wipers intermentent. 2 very dangerous when driving in rain. 3 removed and replaced wipper motor circuit board and cover.

While driving in rainy weather, the front windshield wipers failed. The dealership was notified, but did not resolve the problem. The cause was not determined. Please provide more information.