wipers will come on but will not shut off until the engine is shut off
You may have more than just one problem here, the switch is the most likely problem, however it could also be the motor assembly, there is an internal switch that is no longer serviced that can cause this so your stuck buying a motor assembly, the other is the wiper control module, solid state so there is no repair just replace. Of course all of this is depending on that you have good wiring and not grounded or crossconnected circuits.
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