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Parts for Whirlpool GD5SHAXLT02 Refrigerator - AppliancePartsPros.com

See the attachment for the tech sheet.

Since cleaning the coils seemed to repair it in the past, check that the condenser/compressor fan is running. Perhaps you just moved it a little when cleaning and that helped it start up.

If it is on then check if the compressor is running. You can usually hear it but you should also be able to feel it.

Check if the evaporator/freezer fan is on.

All three of the above should be on together as they are wired in parallel.

Could be that you are in a defrost cycle it usually lasts about 30 minutes but should be completed for sure after an hour.

If it stays off, try moving the temperature control thermostat to off then very cold.

If it then fires up I would replace the thermostat.

If this does nothing, unplug the unit and short the Red to Orange wires at the thermostat together. Make sure thay cannot short to anything else.
Then plug it in.
If it fires up then odds are that the thermostat is bad.

If this does nothing then odds are that the defrost control board is bad.

[COLOR="Blue"]Is it the defrost thermostat I should replace?[/COLOR]
No
Replace the main temperature control thermostat (item 9 in section 10).

Still a bit of a gamble but this is the most likely bad part.

You could try just moving it up/down a bit (not to off) when this problem happens again.
If the unit fires up it adds a bit more weight to it being a thermostat problem.

[COLOR="Blue"]Still sound like the thermostat?[/COLOR]
No.
The more likely culprit is the defrost board.

Unplugging it resets the board so the unit fires up.

I very, very rare cases it could be the thermostat re: the current going through the thermostat windings is holding them closed so removing power lets them open.
But as I said this is unlikely.

It is item 6 in section 10

Part number: AP5326116