Purchased a ML320 2002 with the Rain Sensor feature for the wiper. Sensor is overly sensitive, with wipers going into action with only a few spits of rain. Are there any know adjustments?

No adjustments that I'm aware of. Only thought is maybe something is on the glass which is affecting the reflections on the sensor, such as "Rain-X" or some other water-shedding treatment, or if you can comapare it to a similar vehicle in the rain or mist, and your truck definitely is more sensitive, possibly it's just a problem with the sensor itself.

Gilly