Procedure : Undid 2 plastic nuts, unplugged & removed all motors, then unplugged & removed sensor. Then removed bottle and pulled out all filters in bottle cleaning same with old toothbrush.Used hose to rinse out bottle.
2nd time doing this & on resasembly I had washer fluid low warning. Assumption made I must have dmaged sensor by bending,knocking same.Tried carefully straightening sensor but no change. Tried again & promptly broke it


Hopefully new sensor will sort matters otherwise I have damaged the floaty bit in bottom of bottle. I will know by next week.
So my advice.............Be careful not to cause damage when doing this simple job.