Dishwasher stops mid cycle

[madgearooch]

My Kitchenaid dishwasher model # KUDS25SHBL1 keeps stopping in the middle of the cycle at different times.  Sometimes it stops during the wash cycle (full of water), and sometimes it stops after the pumps drains, no real pattern .  I think it might be heat related because this started about 3 months ago only when I ran the an extended cycle (sani rinse or similar).  It is at the point now where it won't even complete a normal wash cycle.  As soon as it stops I try to cancel the cycle but when I push the botton nothing happens.  I open the door and let it cool off for about 30 minutes and then I can cancel the cycle and it will pump out the water.  One other thing is that once you start the cycle and then open the door, the cycle will not resume where it left off,  you must press the buttons to restart it and it start over at the beginning of the cycle.

[Repair-man]

From your description (nice job!), it sounds like one of 2 distinct possibilities exist for this KitchenAid machine...

I would suspect a loose connection down where the house wiring was tied into the dishwasher first.

After that, I would probably suspect the control. I base my reasons on evidence that I read on the Technical Data Sheet for your model. See what you think and lt us know your findings later.

Dishwasher Electronic Control Assembly Part # 8530929

[madgearooch]

I checked the house wiring and all the connections are tight.  Is there some kind of heat sensor that would shut it down.  Also are you referring to the control panel?

[Repair-man]

There are electronic fuses in the unit (TCO) but they are  mainly in line with the heater circuit and appear to be non-resettable. (I hope you looked at the tech sheet).

The motor on your model has a built-in thermal overload and will drop out if excessive amperage or motor temperature causes the overload to open. It takes awhile for this to reset, as you also described. 

What a technician would likely do if he were there would be to place his voltmeter leads across the motor run windings during operation and monitor the   voltage until the unit cuts out. If there was still voltage to the motor, yet it stopped, there's the problem.

You will notice on the Tech Sheet I provided above that there is also a quick Diagnostic cycle test that you can perform to quickly locate the problem. There is a chart on the right side of the sheet that shows the results from the test and what to look for. If you are not  familiar with voltmeters and such, better stop guessing and call in a pro. It gets expensive throwing parts at something unless you know your target.

[madgearooch]

When running the diagnostic cycle, what am I looking for. I have worked on alot of appliances over the years(washer, dryer, range etc), but I am a little confused on how to run the diagnostic cycle and what am I looking for.  Can you explain that to me.


Thanks

[Repair-man]

The diagnostic cycle is too complicated to go into if the tech sheet did not make sense to you.  You can eliminate the need to do the diagnostic by following my suggestion above:

What a technician would likely do if he were there would be to place his voltmeter leads across the motor run windings during operation and monitor the   voltage until the unit cuts out. If there was still voltage to the motor, yet it stopped, there's the problem

If there is no voltage to the motor when it cuts out, then you know the timer is the problem. A hot motor will automatically stop and you cannot get it to run until it cools off  in 30-45 minutes. An internal overload on the motor controls this feature. Again, there should still be 120 volts showing at the motor when the thermal overload inside of it cuts out. You must catch it "in the act" to check this.