On vehicles with intermittent windshield wipers, the wiper motor circuit board may fail and cause the wipers to stop working at times. Replacing the circuit board should resolve the issue. 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 Jimmy Failed Wiper Motor Circuit Board May Cause Intermittent Wipers to Stop Working
GMC Jimmy Problem
Average Mileage: 146,814 mi (70,000 mi - 217,000 mi)
Windshiled wipers will cut off and then if you shake the motor they will work again.
Visitor, 1998 GMC Jimmy, 188,888 mi
Cut into wire harness and put a on/off switch on the power wire ! It works ! Turn it on turn it off!
Visitor, 1998 GMC Jimmy, 93,000 mi
Same problem. replace the board and solved the problem.
Visitor, 1998 GMC Jimmy, 70,000 mi
windshield wipers work as they want to. Will work sometimes then they will just stop and I have to turn it off and on to get it to work again multiple times. My car is a 1998 gmc jimmy.