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Replacement parts for WHIRLPOOL DU920QWDQ3 | AppliancePartsPros.com

Here is the tech sheet
http://www.servicematters.com/d...0Sheet%20-%203379064.pdf

I need to replace the control board of my Whirlpool dishwasher.
Why? What are the symptoms? What have you done to troubleshoot it?

There are two spring loaded breakers. One of the two has tripped. The other has not.
This is where you loose me. Are you referring to the door latch switches, Item 11 in Section 1?

Do I need to replace the fuse along with the control board ?
In order to know what to replace you have to check the fuse to see if it is blown. It could be that it is all that is wrong with the unit. If it is the fuse the new wiring harness also has to be used. See Item 4 in Section 1.

Or do I replace the control board and just reset the breaker that tripped ?
Again am lost here as I do not see circuit breakers in either the parts or the wiring diagram. If it is the switches, both should close when the door is latched.

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.

Here is a manual which may be useful
https://secured.whirlpoo...e9b3e/$FILE/4322451L.pdf

The reason I need to replace the control board is because the dishwasher failed to turn on. So I had a repairman come out and look at it. He said that the control board needed to be replaced.
If the repairman did not remove the inner door panel then he was just guessing.
The fuse can blow because of excessive current but it is designed to blow because of high temperatures. If the residue near the fuse is soot then it may have blown due to high current. This could be a shorted device or a blown board.

So it appears that the thermal fuse definitely needs to be replaced.
Check it with a meter it should be 0 ohms.

It would seem that the control board also needs to be replaced, otherwise, why would the fuse blow ?
Sometimes they just blow as you can see the replacement is a kit to reduce the fuses doing this. Also could be a device has shorted.
Check the various devices to make sure they have resistance basically you are trying to find out if anything has shorted. Note always remove at least one wire from anything you are measuring for ohms. This ensures that you do not read an alternate/parallel circuit path.

The dual motor is the device that has two spring loaded latches. One latch is released and won't reset in the "in" position. The other latch is set in the "in" position. Is that a normal condition for the dual motor latches ? Are those latches actually circuit breakers ?
Not sure where they should be at rest, check the manual. They are wax motors. Basically this is a plunger in a cylinder filled with wax. You will see on the wiring diagram that each one has a small heater in it. When this heater is turned on the wax melts, expands and pushes the plunger out. Remove power to the heater and as the wax solidifies the plunger is retracted. Sort of like a slow acting solenoid. They run the rinse aid and detergent.

This is what I would do but do not know what experience you have so am not recommending it.
I would check the fuse.
If blown I would wire in a standard 10 amp fuse.
And give it a try.
If it fires up and runs a cycle then you know that it is probably just the fuse that is blown.
Do not run the unit like this, it is just to check the system.
I would then order and replace the fuse ASAP as it is a critical safety device for both temperature and current.
If the 10 amp blows then check the various devices for resistance.
If all are OK then it is probably the board that is shot.

At close to $170.00, I do not know if it is worth putting that many dollars into this fairly old machine unless it is in excellent condition.

I would check both wax motors, pump motor windings and the fill valve.

Also visually check the wiring where it goes from the door to under the unit.

Have you checked both door latch switches to make sure that they both close and when closed they are at 0 ohms.

You could also close them and then check that you have 120 volts between P8 and P7 on the board.

If you do have the correct voltage here then I would put the board at the top of the list.

[COLOR="Blue"]I then measured the voltage between P7 and P8 and got 120 volts. Is the next step to replace the control board ? [/COLOR]

Yes that would be what I would do as it is getting power and will not fire up.