The wipers on my 2000 S430 come on randomly almost every time I drive it. The previous owner had the park relay replaced. If you turn them on and off a few times they will finally shut off. Is there some type of moisture sensor that can be bad??

When you turn the wipers on in that car, there are 3 computers involved!
If you leave the wiper switch in the "auto" position, there are 4 computers involved!

To diagnosis that problem on that model & MOST MB's after 1998 you would need a MB scanner capable of reading codes from those computers & capable of reading live data & activation of that system.

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