Is there an abnormal light buzzing noise from the wiper motor while they are opporating? Try tapping on the control module part of the wiper motor (black plastic cover on the motor held on with a single screw in the center of the cover)as it runs after you have turned off the wipers with something about the weight of a zippo lighter. If the buzzing noise is present and the wipers shut off when you tap on module, the control module has failed. The module is replaceable separate from the motor and should be readily available from both the dealer or an aftermarket parts store. There is a module for atandard wipers and pulse (intermittant) wipers, be sure to get the proper module for your vehicle, they are not interchangeable.
Let me know if this helps or if you have any further questions.
Thank you for your question
Saturday, January 15th, 2011 AT 5:27 PM