My microwave fan and turntable are running when the door is open. I am not sure whether microvave is actually running with the door open, but I can hear the fan humming and turntable turning. If I close the door, the hum disappears. It seems to work properly (ie food is heated). The model is GE JE1540WW 003, and is about 8 years old. Any idea how to fix? Also is dangerous to continue to use, since I am not sure there's microwave when the door is open. Thx.