TIP: A common trouble maker of late has been the dispenser motor freezing up and sticking and not turning to dispense the ice cubes. GE has come out with a couple of boot kits to help prevent the dispenser motors from getting frozen up.
Electronic GE SxS boot #WR02x11295
On very old GE fridge's there is an access panel on the inside of the freezer door that will allow you access to the ice dispenser workings. Please see the picture below. The access panel must be pulled out from the middle until the top clips come disengaged from the top of the liner opening, then lift the access panel off the tabs from the bottom of the liner opening.
GE old fridge's have a front serviceable ice dispenser. Remove the upper front escutcheon ( the part with the writing - it will "pop" off towards you ). The rubber cup pad has to be removed, it also will just come off when you pull it towards you. There are 4 screws to remove to allow you to remove the upper part of the dispenser ,this will give you access to the working parts. See parts break down below....
GE's older SxS refrigerator dispenser.
Small flat screwdriver to pry/ease the bottom part of the key panel loose and out towards you...
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The key panel will come out towards you and ( with power off ) the wires are easy to unplug...
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Remove 4 star screws...
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The whole assy will easily come out towards you...
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You are there...
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The model # is ZISS420DMAS
( this refrigerator had a metal trim around the doors and panels )
The way it worked on my fridge was:
Water filters for GE, Whirlpool, Electrolux/Frigidaire, Maytag, Amana refrigerators.