You refrigerator was made by Frigidaire
Adaptive Defrost Controls Frigidaire Refrigerator
Trouble Shooting and Diagnosing
On the initial plugin, or when power is restored to the fridge after a power outage:
If terminating thermostat is open, the fridge enters a compressor (cooling) cycle.
If the terminating thermostat is closed, the first defrost cycle occurs 1 hour
after initial plug-in.
Maximum defrost cycle time is 24 minutes.
Minimum time between defrost cycles is 6 hours. (compressor runtime)
Maximum normal clock time between defrost cycles is 12 hours.
Maximum time between defrost cycles (in "vacation" mode) is 72 hours.
Vacation mode is not entered unless the door has not been opened in at least
24 hours. Note that the ADC will only enter the defrost mode if the terminating thermostat is closed
. If the terminating thermostat is open when defrost is initiated, the ADC board will wait for six minutes and then return to the cooling mode.
ASSUMING that the fridge has been on and running,
and the terminating thermostat is closed,
defrost is initiated by pressing the door (light) switch
at least five times within six seconds.
The defrost heater should start heating up within 8 seconds.
If the above procedure caused the heater to heat up, the ADC board is probably bad; replace it.
If the defrost heater does not heat up, test the defrost heater, terminating thermostat and cold control for continuity as follows:
Unplug the fridge from the wall. Unplug the ADC board from its connector.
Test the connector for continuity between the following leads:
Defrost Heater = DEF TERM (blue) to DEF OUT (brown).
Terminating Thermostat = DEF TERM (blue) to NEUTRAL (lt blue).
Cold Control = COLD CONTROL (orange) to L1 (black).
Replace the defective component.