int. wipers & headlight wiper

[autounion]

'99 SL500. intermittent wipers not working and right-side headlight wiper/washer out of wack. washer just keeps pumping til reservoir is dry. right headlight wiper out of sync. with left side wiper.

i suspected that sensor on windshield, (rain sensor?) because i could see the box from the outside. supposed to have some kind of cover over it, yes? anyway, i pulled the back cover off it & unplugged the harness. now intermittent w/s wipers work fine!

headlight wipers still keep pumping fluid non-stop until i turn off headlights.

any clues to this? are headlight washer/wiper controlled by this rain-sensor?

thanks.