The windshield wipers may not work intermittently due to a faulty wiper motor control board. Our technicians tell us that lightly taping on the wiper motor when the fault occurs should temporarily get the wipers working again. Some vehicles were recalled for this problem and some were not. You will need to check with your local dealer to find out if a specific vehicle was included.Google+
Car Problem Reports
GMC Suburban 1500 Windshield Wipers May Fail Due to Faulty Wiper Motor Control Board
GMC Suburban 1500 Problem
Visitor, 1993 GMC Suburban 1500
Wipers, once turned on will run after being turned off, or the truck motor is turned off. Sometimes this time lag is 10-15 minutes. Wipers also fail to respond to variable speed settings and delay settings.