GE GSS20 Series, Technical Service Manual

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Diagnostic Chart
FREEZER
DISPLAY
FRESH FOOD
DISPLAY
DIAGNOSTICS RESULTS COMMENTS
0 2
Communication check between
Temperature Control and Main Control
“P” on freezer display if OK,
“F” if problem is found.
0 4
Communication check between
Dispenser Control and Main Control
“P” on freezer display if OK,
“F” if problem is found.
Dispenser models only.
0 5 Encoder Test
As the knob is rotated, the
display will show the
corresponding setting.
Only for models with
temperature control
knobs.
0 7 Control and Sensor System Test
Checks each thermistor and
displays “P” for pass and “0”
for fail.
See Note 1.
0 8 Duct Door Test
Opens the dispenser duct door
for 10 seconds, then closes.
Only for dispensers with
5 or more touch pads.
1 0 Dampers Test
Opens each damper, pauses
briefly, and then closes.
Includes Custom Cool
dampers if applicable.
1 1 Fan Test
Cycles through each fan for 10
seconds.
1 2 100% Run Time
Sealed system on 100% of the
time. Times out after 1 hour.
1 3 Prechill Test
Starts Prechill mode. Unit
returns to normal on its own.
1 4 Defrost Test
Toggles on the Defrost cycle.
See Note 2.
Must press again to turn
heaters off. See Note 2.
1 5 Main Control Reset Causes a system reset.
1 6 Exit Diagnostic Mode
Causes a temperature control
board reset.
Note 1. Display order is: #1 = Fresh Food 1, #2 = Fresh Food 2, #3 = Custom Cool, #4 = Evaporator, #5 = Freezer.
Thermistor test results are: P = Pass, 0 = Fail, S = Short to 5 VDC, B = Bad amplifier (replace main control).
Note 2. You must enter the defrost test again to toggle the defrost heater off at the end of the test.
The heater will not come on if the evaporator thermistor is warm.
Refer to Service Guide 31-9072 for additional information.