If you had a windsheild replacement,and now your wiper,s are not working properly,the sensor,in the mirror,shoot,s a enfered light through the glass,the factory window,was designd to reflect off of it,some replacement wind sheild,s do not have the correct temper glass ,to do this,
Some aftermarket brand windshields don't work with the BMW system. Go back to the auto glass shop to get it rectified.
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