My Samsung upper ice maker stops after making one cycle of ice. When I run the diagnostic code check, it shows the I/M sensor error (upper right top digit of dosplay not lit). If I allow the ice tray to freeze & push the reset button in the ice maker, the display chimes & it will cycle through & eject the ice, followed by the ice tray refilling. After the tray fills with water, I get another chime tone from the display. What does this error mean about a sensor problem? Where is this sensor located & how do I test it?