I have an intermittent problem with the wipers. Sometimes when I wash the windshield they won''t stop wiping until I pull the fuse or turn off the ignition. After I spend some time trying to figure out where the problem is, they start working normally. I figure the problem is either with the wiper switch or the wiper motor assembly. I searched this forum for a trouble isolating procedure and did not find one. I found a circuit diagram for the wiper on this forum and I have studied it, but I can't make sense of how the park relay arm controls the several contacts that are connected to it by dotted lines and the solid state timer relay. I would like to know how to tell if the defective part is the switch or the motor assembly. My Haynes manual says if they won't stop, disconnect the wiring from the wiper control switch and if they stop, replace the switch. If they keep running, replace the motor. That does not make sense because if you disconnect the wiring that connects the switch to the motor, it is always going to stop because it can not get power. Haynes does not say which end of the wiring to disconnect, the switch end or the motor end but it looks to me like the motor is going to stop no matter which end is disconnected. The parts are expensive and difficult to install, so I want to know which is defective before I replace it. I tried to drag my copy of the circuit diagram to this post but it would not work.