If you take off the plastic cover just below the window outside of the car, you'll see the tunnel for the air to flow through and down into the blower housing. Sometimes that housing will get so backed up with leaves and debris that water will stagnate in there and raise to a level that overflows into the blower housing.
Some of the black plastic covers are two piece and others are one piece. If it's a two piece, it's easy to take off by removing the trim clips that hold it down. If it's one piece, you have to take off the wiper arms.
As for the wiring, even though it's covered, it could have rubbed through at one spot. Check from the back side of the light socket as far as you can trace the wires and see if there's any spot in the electrical tape/split loom that looks like it's been rubbed through.