This is from the owner's manual:

"To activate the rain sensor: Move the lever to position 1 with the ignition key in position 1 or higher. The wipers travel once across the windshield, regardless of the weather conditions. You can leave the lever permanently in position 1."

In other words, if that's true, I have to disagree with you. If it's not raining, when you engage the rain sensor position, it should swipe once, then stop. But I think you're right about it parking in that position, if the rain sensor is on. A fault in the rain sensor system would explain why it's doing that. Somehow though, I doubt it's the sensor itself.

In the rain, it behaves erratically. It always swipes twice in a row, and at no specific interval, regardless of how hard it's raining. This post sounds exactly like my problem.

So far I have seen the following suggestions:

- Replace wiper relay. Doing this tonight if I can find one locally.

- Take the blades off the motor, turn the wipers on to engage the motor, turn them off when it stops, then put the wipers back on the correct spot. I don't think this would fix my wiper position, since they do swipe all the way up and down, it's just that they "park" in the wrong spot.

- Replace the wiper motor. I hope that's not it as that's not a cheap fix.