Service Manual

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4. Defrost Termination
9) Check that the components restart after defrost termination.
Refrigerator: DTh reaches 44°F (6.6°C). EvapFM icon stays on and EvapFM continues.
Comp and ConFM energize. If not, check DTh status. See "II.D. Thermistor Check."
If DTh ohm reading is in proper range, and components do not energize, check for
115VAC at CM 1 (C) (V) to neutral (W). If 115VAC is not present, replace CM. If115VAC is
present, check component continuity and replace as needed.
Freezer: DTh reaches 77°F (25°C). DH de-energizes. "dEF" continues on display.
3-min. later, Comp icon turns on and Comp and ConFM energize. EvapFM icon turns
on and EvapFM energizes once DTh reaches 15°F (-9°C) or 4-min. EvapFM delay timer
terminates. If not, check DTh status. See "II.D. Thermistor Check." IfDTh ohm reading
is in proper range, and Comp and ConFM, or EvapFM does not energize, replaceCM.
15min. after EvapFM energizes, cabinet temperature appears on CM. Ifcomponents fail
to start, check continuity, replace as needed.
Legend: CM–control module; Comp–compressor; ConFM–condenser fan motor;
CTh–cabinet thermistor; DH–defrost heater; DS–door switch; DTh–defrost
thermistor; EvapFM–evaporator fan motors, MH–mullion heater; PH–perimeter
heater
D. Thermistor Check
The cabinet thermistor is used for cabinet temperature control and the defrost thermistor
is used for defrost cycle termination and evaporator fan motor control.
• Refrigerator: Defrost termination is 44°F (6.6°C).
• Freezer: Defrost termination is 77°F (25°C).
• Freezer: Evaporator fan motor initiation after defrost is 15°F(-9°C) or
4-min. Evaporator fan motor delay timer terminates.
• Evaporator fan motor high-temperature control:
Refrigerator: Defrost thermistor at or higher than 50°F (10°C).
Freezer: Defrost thermistor at or higher than 32°F (0°C).
Thermistor resistance varies depending on temperature. The control module monitors the
thermistors to control system operation. No adjustment is required.
To check thermistor resistance, follow the steps below.
1) Unplug the appliance.
2) Remove the front panel, control panel, top louver, and evaporator cover.
3) Remove the thermistor in question, then immerse the thermistor sensor portion in a
glass containing ice and water for 2 to 3 min.
4) Disconnect the thermistor connector from the control module.
5) Check the resistance between the wires at the thermistor connector. Normal reading is
within 16.0 to 16.7 kΩ. If outside the normal reading, replace the thermistor.
6) Reconnect and replace the thermistor in its correct position.
7) Replace the evaporator cover, top louver, control panel, and front panel in their correct
positions.
8) Plug the appliance back in.