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Replacement parts for MAYTAG MSD2454GRW Ref - SXS/I&W | AppliancePartsPros.com

Here is a service manual
http://www.servicematters.com/maytag_library/docs/16010154.pdf

The parts shows that this unit has a defrost timer (Item 13 in Section 2) and not a adaptive defrost board, so first you have to which one it actually has.

If it is a defrost timer I can think of a number of reasons why the tech said "defrost board"

1. They did not do any troubleshooting and just assumed that the board failed. In this case I would not allow this person back to repair the unit as their service ability is poor at best.
2. The parts breakdown is incorrect. The unit is a late model in this units build and the timer has been replaced by a defrost board.
3. The service person misspoke and actually meant defrost timer.

I would confirm that it is a defrost problem. Remove the rear cover in the freezer section and check the evaporator coils. If they are heavily iced/frosted up then it is a defrost problem.

This can be cased by the timer/board, the heater or the defrost thermostat.
We need to know if it is a board or timer before proceeding.

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

Manually force a defrost cycle by turning the defrost timer cam (Item 13 in Section 2) till the fans and compressor turn off.
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, re: it is probably stalling during it's rotation so is never getting into a defrost cycle.

If not on.
Unplug the unit.
Remove the wire for one side of the heating element/thermostat combo (Item 13 in Section 4 ) from the wiring and measure it for continuity, usually around 20 ohms or so.
Note that the thremostsat 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.

[COLOR="Blue"]I tried to manually force the defrost cycle, but it didn't work. After turning until I heard the 1st click, the fan & compressor went off and came back on after a couple of minutes. I did this several times with no result.[/COLOR]
Does sound like the heater/thermostat combo needs replacing

[COLOR="Blue"]I didn't get anything on the multimeter. I don't know if this is because something is bad or because I don't know what I'm doing. I'm not familiar with a multimeter.[/COLOR]
FYI a multimeter is a fairly simple device. It has a battery when you measure ohms the voltage from that battery is applied to the device you are measuring and the the meter measures the current and then changes it to resistance.
I always short the ends of the meter leads together before measuring ohms. If you get a 0 you know that the meter is working.

[COLOR="Blue"] I'm not sure if I'm supposed to touch the outside of the wire or stick the leads inside the wires connector.[/COLOR]
You have to make contact with the metal connections so you have to stick the meter leads into the connector. If the lead tips are too big to reach the metal plugs in the connector stick a couple straightened paper clips, small nail etc. into the connector and then measure. Just make sure whatever you use do not touch each other.

[COLOR="Blue"]I found some info online that said to take the negative lead and insert it into the orange wire/connector coming in from the back of fridge and postive into the heating element/thermostat connector. If this is correct, I didn't get a reading.[/COLOR]
Not sure I understand the above.
Unplug the connector going to the heater/thermostat combo and measure across the contacts in the plug on the combo side.

You are welcome

And thanks for getting back to us. Now when others search for a similar problem they will see what actually worked instead of just suggestions about what could be the cause.

PS: The picture was definitely worth a thousand words.