Mephistocrat

The wipers on my 97 SS operate normally when switched on -- they pause at the proper position, sweep across the normal range of movement and have no abnormal behavior when they are active. When you switch them off however, they complete one extra cycle and then park straight up on the windshield.

I did several searches and most everything pointed to the circuit board jobbie on the wiper motor, so I bought a used motor+board assembly from a salvage yard, installed it and the same problem persists. Both the old and "new" motors have all the respective pieces and springs with no visible distinction between them. I suppose it's possible that I inherited the identical problem from another car's wiper motor, but I'm suspecting it's likely something else.

Could there be something in the switch/stalk on the steering column that could cause this behavior? What can I do to isolate and test further? Thanks in advance!