Whirlpool Modular Ice Maker Repair Guide
For general information visit the "How Ice Makers Work
On Whirlpool Ice makers most of the ice maker's parts can be checked for resistance through the front of the ice maker.
Note: The refrigerator must be unplugged for any resistance readings to be successful and prevent damage your volt meter.
Set your multimeter to measure resistance, next insert your meter leads into the test points to check the corresponding ice maker component.
L and H will measure heater's resistance it should be about 72 ohms. (Some resistance not open)
L and M will check the motor resistance (Somewhere between 300 and 4400 ohms) (Some resistance not open)
V and N will check the resistance of the water valve coil (approximately
300 ohms). This one is nice because you can test the water valve without having to pull the refrigerator away from the wall. The coil can give a positive resistance reading and still be clogged or not opening for some other reason. If the water valve tests open, it definatly needs replacement, this almost never happens.
Ice makers do not have any kind of a water level sensor like a washing machine or dishwasher does; instead they fill for a set period of time as the rotation of the timer temporarily energizes the water valve. Ice makers are set at the factory for average household water pressure; however, if you start to have problems with individual ice cube groups connected along the top, icicles hanging from the ice maker, your ice container floor covered with ice, or small cubes, you can correct the problem by adjusting how long the valve is energized with a screw located on the ice maker module. Adjustment is clockwise to reduce fill time and counter clockwise to increase it.