Samsung dmr78 dishwasher will drain, fill, open the soap dispenser and otherwise go through its cycle. It will not move any water in the unit to wash, the motor gets HOT, makes a slight buzzing noise

The soap dispenser is probably faulty. Wash times can vary. The main controller will determine the wash time and will change according to water temp when filling, time it takes to fill, etc. Check and make sure the filters at the bottom are clean.

Check for the right amount of water in tub. In this unit close to the lip of the tub after fill. If water fill is correct check movement of lower spray arm. Other possibilities delayed action of dispenser from defective wax motor. Most probable is wash motor. Start unit after fill and when was starts, open door and see if water is being pushed to the top rack and dripping from the top of tub. Motor is easy to install.

there could be many solutions from not enough water in the dishwasher
to the piece on black backing in between the door and inner linning has warmed up and slide down restricting the soap door from opening
the lack of water could be from a defective water fill valve or a restriction in the drain line holdingf the drain valve open alowing water to escape
when the machine fills open the door see how much water is in it close the door wait 2 min open the door again if water went down the problem is arestrictioninthe drain valve (water should fill to touch the element in the bottom i hope this helps

Be sure that nothing on the top rack is interesting with the door opening. Next place in unit in the wash mode. Let it fill and start washing. Open door and you should have water standing just below the lip on the wall of the unit below the lower rack. If so you are full of water.

Next is to ensure your washer rotating arms are not plugged. The very end of the upper and lower arms spray on the door to wash the soap out. If the are contaminated you will have to remove them and clean the out.

Lastly, the dispenser is operated by what is called a WaxMotor. Simply put it is a small amount of wax contained in a tube with a piston inserted. There is then a heating element around the tube. When it appmys heat the wax expands and pushes on the piston which I turn releases the door to be opened by its spring.

These can go bad and open too late in the machines cycles. It is located in the door and unless you are quite handy I would recommend a qualified technician.

Kitchenaid lists 130 dishwashers with this model. Need the rest of the number
KUDSO1DLxxxx
Back in the day, when I worked on K Dishwashers, the drain valve was the problem typically.
It would get a piece of glass, from broken glass or other item, or a toothpick, whatever stuck in the drain valve. It would not completely close. During the wash cycle, water would be trickling down the drain and by the time the soap dispenser opens, the water would be gone or nearly gone.
Check this. When you hear the dispenser snap open, stop the dishwasher and open the door.
If you have little or no water, you are losing the water during the wash cycle.

Let me know.
Gary

First thing to check is to make sure the dishwasher is getting water.

1. Check the water temperature. Should be 125 to 140 F.
   
2. Check pump re-circulation., Listen, see if it sounds like it is spraying the water around with enough pressure.
   
3. Check water level when the fill cycle has completed. Should be just under the heating element. If not, possibly need to replace the water inlet valve.
   
4. Check the spray arm and pump cover for splits or leaks.
   
5. Check to make sure dishwasher is draining after each cycle. There should only be a little water in the bottom of the tub.
   
6. Make sure the dishes are loaded properly, or dishwasher is not overloaded.
   
7. Possibly try a different detergent. Some liquid-gels will bubble and a pump cannot pump bubbles.
   

Scrape away large pieces of food, bones, pits, toothpicks, etc. Burned on food should be loosened before loading. Empty liquids from glasses and cups. Foods such as mustard, mayonnaise, vinegar, lemon juice and tomato products may cause discoloration of stainless steel and plastics if allowed to sit for a long period of time. Unless the dishwasher is to be operated at once, it is best to rinse off these food soils. Load racks so that large items do not prevent the detergent dispenser from opening. If the dishwasher drains into a food disposer, be sure disposer is completely empty before starting the dishwasher.
just click on the above questions for more help the answer will come to the screen

1. A common leaking trouble maker
   
2. Another common leaking trouble maker - especially for leaking out of the door area
   
3. Can I use a rubber or plastic hose for the hot water on my built in dishwasher ??
   
4. Some common pump assembly pictures...
   
5. Dishwasher Basics
   
6. Dishwasher child lock help
   
7. Dishwasher soap notice
   
8. Draining and washing help
   
9. Help for storing an appliance
   
10. How to remove the access panels
    
11. I just installed my food waste disposal, now my dishwasher will not drain, what could be wrong??
    
12. I moved and lost the tap adaptor for my portable d/w, help!!
    
13. Important disclaimer
    
14. I would like to try to install my own dishwasher
    
15. Loading your dishwasher help
    
16. Motor and pump assembly screw and impellor help
    
17. My dishes are not as clean as they used to be, what might be wrong?
    
18. My dishwasher racks have rusted.
    
19. My dishwasher will not fill with water
    
20. My dishwasher will not start
    
21. My soap dispenser will not open
    
22. Sand like deposits inside the glasses and d/w
    
23. Some common soap door dispensers breakdowns
    
24. Some common soap door dispenser door springs
    
25. Stainless Steel Cleaning
    
26. Strange grinding noises and not washing properly
    
27. The dishwasher doors falls down
    
28. White filming on the glasses
    

If you are you using a liquid soap or packets that will be the main problem.If your unit fills with water circulates the water and drains the water,and also heaters are working then you probally need to change to cascade powder soap.The film on the dishes is soap.The unit has so much build up in it that when it gets to the rinse cycle it is rinsing dishes with soapy water.You need to get 2 medium bowls fill both 2/3 up with white vinager,place one in upper rack and one in lower rack and run unit on longest cycle letting the vinager splash out during wash.do this with no soap and no dishes.Having soft water will allow you to use less soap.

is the drain hose to low causing the dishwasher to fill and drain at the same time,if the water level is to low the motor wont wash the soap out of the dispenser.hope this helps

If the dispenser door is opening, then it is working properly. You have some kind of problem during the wash causing the soap to not wash out of thye dispenser. Either the pump is clogged or not pumping for some reason, there is not enough water coming into the unit or it is draining for some reason, or the water is sudsing up for some reason, usually rinse aid leaking into the water.

Start a wash cycle and let it fill completely with water then open the door and see how much water is in the tub. It should be just under the heater.
If it is ok, let it wash a few minutes then check it again to see if there are a lot of suds. If so, there is usually a leak in the dispenser.
Post back and let me know what you find.
Thanks/Mike