Not really sure what's wrong with my wipers-- my
passenger side works but the driver side doesn't go back
down. It actually goes past my window when I first turn
them on and hits the mirror and gets stuck since it's not on
the windshield anymore. It's really frustrating to drive in the
pouring rain and having to sit and look through the
passenger side of the windshield, also very dangerous!!
It sounds like the wiper arm skipped on the spine shaft on the driver side causing a "calibration" issue on the wiper arm. Typically there is a plastic cap where the wiper arm mounts to the shaft at the bottom of the arm. Pop the cap off and there should be a nut that secures the arm to the shaft. Loosen the nut and see if the wiper arm can be re-positioned to where it should be and then re-tighten.
Mine does that too from time to time. The spines may well be stripped. You could replace some parts, or just carry a wrench with you and when it acts up tighten the nut a bit more. Follow Mark's advice for now so you can keep driving the car. You likely don't have to pull the arm off though. Just loosen the nut a bit and push the wiper back into its proper position, then tighten the nut down again.
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