MA1, 1 year old, told me to calibrate vision sensors. Has got to be done on a computer, dusted mine off and tried to remember how to turn it on! Eventually downloaded assistant 2, fairly easy to recalibrate, success! Two questions. 1, This warning shown after fitting strobe to underside battery ( not very near to sensors. Still showing after removal of strobe) the cause? 2, is it normal for the vision sensors to occasionally need calibrating? Not a life or death question but thanks in advance for any feedback ?