The round knob in between the two over-ride valves is to turn the wipers OFF/On, so you can change the wiper blades. The push/pull knob will open/close the door, but will not effect the wiper operation itself.
The wiper switch MUST be grounded to work...that is why you see sparks when you touch it to the bezel...it should be grounded to the bezel. A lot of folks will run a dedicated ground wire to one of the screws that hold the switch to the bezel, to make sure the switch is properly grounded.
If you bezel is not getting a good ground contact when it is screwed to the dash, it can cause wiper problems, which is the reason for the dedicated ground. So...make sure the switch is grounded, and be sure the wiper "Stop" knob is turned to the correct setting. The "Stop" knob will allow you to turn the wipers on, and turn the knob to stop them in mid-swipe, so you can easily change the blades. If the knob is inadvertently turned, then the next time you want to use the wipers, the door will open, but the wipers will not move. More than one feller has spent hours diagnosing a wiper problem only to discover the knob had been turned!
hth
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Joel Adams
C3VR Lifetime Member #56
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