Don't snap the new switch back into the door until you test the switches, same with the rear - if needed.

When you get the old switch back home, take it apart very carefully. There are little springs that get lost easily. You will find a lot of dirt and probably a broken contact. A window left partly open allows rain to fall directly on to the switch panel.

The 850s have all of the window switches in the center console and those who drive with a can of beverage will notice that the drop on the rim of the can gets splashed off and into the window switches. That drop will eventually evaporate and turn into syrup inside the switch.

Klaus
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There is no present time, just the past and future