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Replacement parts for WHIRLPOOL GD25DIXHS02 | AppliancePartsPros.com

Here is the tech sheet
http://www.servicematters.com/docs/wiring/Wiring%20Sheet%20-%202198693.pdf

You may not have to get at the defrost timer.
See in the tech sheet on how to force a defrost cycle.

First remove the evaporator cover in the freezer so you can see the coils.
Not 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 a defrost cycle.
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 timer 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 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.

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.

I have an ohm meter. It is not easy to get to the back of the unit. I touched the ohm leads to insure it registers resistance. When I disconnect one side and try to get a reading, I get none. Is ther eanother way to check the heater element before removing it. IT seems liek it woul dnot be an item that would fail.

Just thought of something. If the heater coil is the issue can I remove it and check it by just running 120 v through it to see if it heats?

[COLOR="Blue"]yse, I did this and it does not work.[/COLOR]
Strange that you could not force a defrost cycle.
This may indicate that the defrost timer is also shot but I would change the defrost element first.

[COLOR="Blue"]and it does not appear to have any resistance.[/COLOR]
Just to clarify as some people say it has no resistance when there meter reads a zero. When in reality the meter is just on too high of a scale and the device is OK
So if you are reading infinite resistance (an open) then the heater is toast.

I would also check the defrost thermostat, it should be 0 ohms when frozen.
Also if it looks bulged out I would replace it as water has gotten into it and it will fail in the near future.

Thanks, I will take out the element first and double check the resistance. I cleaned the ice from everything and plugged the frig back in and it gets cold, so I know I have the correct general problem area identified.