GE Electronic Icemaker Technical Service Manual

GE Consumer Home Services Training

TECHNICAL SERVICE GUIDE

Electronic Icemaker

Pub # 31-9063  8/00

!

IMPORTANT SAFETY NOTICE

The information in this service guide is intended for use by
individuals possessing adequate backgrounds of electrical,
electronic and mechanical experience. Any attempt to repair a
major appliance may result in personal injury and property
damage. The manufacturer or seller cannot be responsible for the
interpretation of this information, nor can it assume any liability in
connection with its use.

CAUTION

To avoid personal injury, disconnect power before servicing this
product. If electrical power is required for diagnosis or test
purposes, disconnect the power immediately after performing the
necessary checks.

RECONNECT ALL GROUNDING DEVICES

If grounding wires, screws, straps, clips, nuts, or washers used
to complete a path to ground are removed for service, they must
be returned to their original position and properly fastened.

GE Consumer Home Services Training

Technician Service Guide

Copyright © 2000

All rights reserved. This service guide may not be reproduced in whole or in part
in any form without written permission from the General Electric Company.

Electronic Icemaker

Beginning in the Spring 2001, a newly
designed icemaker will be introduced in
several refrigerators. This service guide will
help you become familiar with the icemaker
and its operation.

The icemaker contains several new and
innovative features. It has an electronic
control board, an on-off switch, a seven ice
cube mold, a lever style feeler arm and a
thermistor to monitor temperature.

The control board contains two sensors
(Hall effect sensors), that are similar to an
electronic reed switch. The sensors are
activated by magnets and are used to assist
in controlling icemaker operation. One
magnet, attached to the end of the ejector
arm, allows the control board to use magnetic
sensing to determine if the motor has reached
the home position. The second magnet,
located on the ice sensing arm (feeler arm),
lets the control know whether the arm has
reached a fully extended position.

MAGNET 1

MAGNET 2

To access the
control board and
other components
within the icemaker,
lift and remove the
plastic plug at the top
of the cover. Remove
the Phillips screw
holding the cover in
place.

The control board is held in place by three
Phillips screws. All wiring is connected to the
board by plug-on terminals.

The on-off rocker switch allows the
icemaker to be turned off. When the switch
is set to on, a green LED on the right side of
the cover will light to show power is on. The
LED is also used to indicate certain icemaker
fault conditions, such as an open or shorted
thermistor, or a harvest cycle longer than 30
minutes. When a fault occurs, the LED will
blink 1/2 second on, 1/2 second off indefinitely
until the icemaker is turned off.

POWER LED

1

The feeler arm moves horizontally. A full
ice bucket will prevent the arm from moving out
to the fully extended position, stopping the next
harvest cycle until ice cubes are removed and
the arm is able to swing out completely

FEELER ARM

FULLY EXTENDED

The thermistor is mounted in the mold body,
directly behind the control housing. The
thermistor provides two functions: to measure
the ice temperature during freezing and for
water level detection during fill.

Freeze

The “Freeze” cycle is the period where
the icemaker is waiting for the cubes to freeze
solid. This period of time is based on an
algorithm programmed into the electronic
control. The control makes these calculations
once per second and takes into account the
thermistors current resistance value and the
rate of resistance change. As a result, freeze
times vary based on refrigerator control settings
and environmental conditions (door openings,
room temperature, etc.) but average
approximately 75 minutes for each drop of 7
ice cubes.

Harvest

The “Harvest” cycle will begin when the
freeze algorithm has been satisfied and the arm
is in the “out” or “fully extended” position. If the
arm is in the “in” position when harvest is to
begin, a delay of 3 minutes will be added once
the arm moves to the extended position. This
3 minute delay allows drawer type ice buckets
to be removed for up to 3 minutes without
starting a harvest. The 3 minute delay will begin
again if the arm goes back to the “in” position
anytime during the delay period. The arm is
spring loaded and will go to the out position
unless it is being held in position by an obstacle
such as an ice cube.

THERMISTOR

The normal icemaker sequence is to fill the
mold with water, wait until the water is frozen,
harvest the ice and then repeat the cycle. To
accomplish this, three cycles are programmed
in the electronic control: Freeze, Harvest and
Water Fill. The control also contains a Power­On Diagnostic Test mode, a Harvest Fix mode,
a Fault mode and a Service Diagnostic Test
mode.

SPRING

PHILLIPS

SCREW

At the start of the harvest cycle, the mold heater
will be turned on. One second later, the motor
will start. The heater will remain on until the
mold temperature is above 35.6°F (2°C) and a

2