Windshield wiper question

When I bought my 2006 Hatchback, there were a few issues. One is the windshield wipers. I've used WD40 and 3-1 oil to loosen up the corrosion on the arms and they wipe now, but there is something wrong with either the switch or some sort of controller (if there is one). When I turn the switch to INT, it does nothing. When I turn it to the other two positions, it will turn on, but turn it back to INT or off, the wiper stops right where it is. I have taken off the switch and the contacts are clean.

So, is this a switch issue, or is there a controller down the line that needs replaced. Thanks in advance for the help.

It could still be the switch, just cause the contacts are clean diesnt mean its good, what you need to do is test all the wires in the wire harness that goes from the switch to wiper motor for continuity

Is the multi-use relay the controller for this sort of thing, or is the controller in the switch itself? I have no testing tools at the moment, and this is such a simple fix one way or the other. My turn signal relay is working intermittently now as well and will be replaced soon. Thanks in advance for the advice.