To start, let me say that I have done my homework on my Whirlpool WSF26C3EXF01, MGR date 10/12, that I bought used . The water valves work and the motor on the ice maker works. The optical sensor stays on continuously for a few minutes when I reset the power, then goes off. The arms are at 10 o'clock and 2'oclock position and the icemaker has not cycled. When I reset the power the red light goes on, it turns on when the flap door is closed and off when the flap door is open. Then a few minutes later the light stays off and the icemaker has not cycled. Can you help?