I find if it is barely drizlling on a cold morning, like this morning, the wipers will run continuously until the cabin air warms up. I think condensation forms on whatever the sensor is. After the interior warms up, they work as they should. I have two black thingies attached to my windshield in front of the rear view mirror. I am guessing one is the rain sensor. What's the other? 2001 E430

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Thank You!
Fred
2009 ML350
2004 SL600
2004 SL500
1996 SL600
2002 SLK32
2005 CLK320 cabrio
2003 ML350
1997 C280 Sport