Before testing the thermostat, unplug the refrigerator
to avoid an electrical shock hazard.
There are
two types of ice makers, modular and component models. Both allow
you to test and replace the thermostat individually. To determine
which model you have remove the outer face plate. If there is
knob, pull it off first, then pry off the face plate with a small
screwdriver.
A modular
unit will have several holes in the module's face plate each marked
with a letter. These holes are for test probes. A component unit
will usually have exposed gears and no testing holes.
If yours
is a modular ice maker, click here to skip ahead for modular
instructions.
Component Ice Maker
It is easier
to work on this type of unit by first removing the entire ice
maker from the freezer compartment. The unit is usually mounted
to the freezer case by two or more screws. Remove the bottom screws
first. While supporting the ice maker, remove the remaining top
screws. Unplug the ice maker from the freezer cabinet if you have
not already done so.
The inner
mounting plate is held in place by two or more screws. Near the
edge where the shutoff arm is located, a pin (labeled "A" below) protrudes through the plate. This pin has a spring under
the mounting plate. Reduce the tension on the spring by moving
the shutoff arm down and next to the ice maker. Remove the mounting
plate.
Before testing the thermostat, unplug the refrigerator
to avoid an electrical shock hazard. 
