Service Manual

26
2. Evaporator Frozen Up
Evaporator Frozen Up - Possible Cause
1.
Evaporator
a)
Dirty.
2.
Evaporator Fan Motor
a)
Fan blades binding.
b)
Defective.
3.
Defrost Thermistor
a)
Out of position or defective.
4.
Control Module
a)
Defective.
5.
Refrigerant Charge/Refrigerant
Lines
a)
Low.
b)
Component restriction (TXV, cap tube, drier).
6.
Defrost Heater (freezer)
a)
Defective.
3. Defrost
Refrigerator Defrost Fails to Initiate - Possible Cause
1. Control Module
(2-hr cumulative compressor run
or 2-hr continuous compressor run
defrost timer)
a) Defective.
Refrigerator Defrost Fails to Terminate - Possible Cause
1. Defrost Thermistor (Conrm DTh
status. See "II.D. Thermistor Check.")
a) Defrost termination temperature 44°F (6.6°C) not achieved.
b) Defective.
2. Control Module a) Defrost thermistor connection loose.
b) Defective.
Freezer Defrost Fails to Initiate - Possible Cause
1.
5-hr. cumulative Comp run or
4-hr. continuous run defrost timer
terminated
a)
Check compressor operation. See "1. Not Cooling."
2.
Control Module
a)
Defective.
3.
Defrost Thermostat
a)
Open. Cut-out: 120°F±5°F (49°C±3°C), Cut-in: 70°F±5°F
(21C±3°C)
Freezer Defrost Fails to Terminate - Possible Cause
1.
Defrost Heater
a)
Defrost thermostat open.
b)
Defective.
2.
Defrost Thermistor (Conrm DTh
status. See "II.D. Thermistor Check.")
a)
Defrost termination temperature 77°F (25°C) not achieved.
b)
Defrost thermistor connection loose.
3.
Control Module
a)
Defective.