Toyota corolla parking sensor problem

[igix]

toyota corolla front right side parking sensor is beeping even in drive mode while driving and also when there is no one is around it is beeping. Has any one had such issues

[forkingabout]

Isn't any ice or debris stuck on the sensor? 

[igix]

I tried cleaning it ,it is the front right sensor that beeps and shows in dashboard asking if want to temporarily dismiss 

[50p]

I had this happen after the free wash at the main dealers after my last service. (car, not me) Eventually it resolved itself but was changed under warranty