[FloridaRay]

Warm fridge while lower freezer drawer cold and making ice. Fridge temp control
works - opens and closes but no airflow. No frost on any coils or water in drip pans. Condenser fan works. Thanks for any help. Ray

[FloridaRay]

Update. Back of freezer frozen. Back of inside of freezer that is. Defrosted and now have cold going to fridge. At least for now.

[denman]

Here are your parts
Replacement parts for MBF2556KEQ1 models | AppliancePartsPros.com

See the attachment for the tech sheet.
Replacement parts for MBF2556KEQ1 models | AppliancePartsPros.com

First remove the evaporator cover in the freezer so you can see the coils.
Do not let them de-ice.

If yes.
Manually force a defrost cycle,see the tech sheet. When the fans and compressor turn off you are in defrost.
Now check the defrost heater to see if it is on.
Be careful you do not want to burn your fingers.
If the heater is on then the control board needs replacing.

If not on.
Unplug the unit.
Remove the wire for one side of the heating element from the wiring and measure it for continuity, 30 ohms or so.

If the heater is OK
Remove one wire to the defrost thermostat and measure it, should be 0 ohms when frozen. Note that it opens just above freezing so must be frozen to check it. Also inspect it, if it is bulged at all replace it even if it measures OK.

If both the above are OK then odds are the defrost timer contacts are toast.
Best way to test this is a live test to see if you have 120 volts across the heater/defrost thermostat combo.