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Replacement parts for WHIRLPOOL GS5SHAXNQ00 REFRIGERATOR | AppliancePartsPros.com

Here is the tech sheet, see attachment

[COLOR="DarkRed"]I suspect bimetl-def but not sure what else.[/COLOR]
It could be the control board (Item 18 in Section 11) or the heater itself (Item 33 in Section 11). The bi-metal is Item 6 in Section 9.

First remove the evaporator cover in the freezer so you can see the coils.
Do not let them de-ice.
If they are heavily iced/frosted over you have a defrost problem.

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, usually around 20 ohms or so.

If the heater is OK
Remove one wires 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. Or you could jumper it using TEST and TERM connections.

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

If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity
1. Always remove power from the machine otherwise you could blow your meter.
2. Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
3. When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale's dynamic range.

There is a good STICKY at the start of this forum about it's use.

[COLOR="DarkRed"]How does bimetl-def disconnect?
Do wires pull out or are they soldered? [/COLOR]
As you can see it is part of the wiring harness (hard wired) so it has to be cut out.
Cut the wires close to the bi-metal and then use a couple wire nuts to attach the new part.
Then use s zip tie to attach the wires somewhere away from the heater with the wire nut open end facing down so water does not get in them.
Some people also like to fill the wire nuts with silicone as an extr protection. If you do this I would first check that you can get a defrost cycle to run.