My problem is that the dishes on the top rack are not getting clean. Dishes on the bottom are ok but there is food residue left on those on the top rack.

Check to make sure there is no food left at the bottom of the rack, then check to make sure you are adding the correct dishwasher soap that Samsung recommends to use with the dishwasher. If this is not working you could try using heavy duty dish washing cycle or try rinsing off your dishes before placing them into the dishwasher this reduces food buildup at the bottom of the dishwasher and helps clean your dishes better

Your screens are plugged with food residue in the bottom of the unit. clean it out. You can use 1 gallon of white vinegar for your wash after you clean the screens. Start your washer to fill with water but after the water starts, open your door and pore all of the gallon in the unit. Let it now run for 4 minutes and stop it by opening the door. Leave the door slightly open for 1 hour. close the door and let the cycle continue for 4 more minutes. open the door and repeat it a couple of more times. Let it sit all night with the vinegar in it and in the morning - close the door and let the cycle continue to the end. This should help soften and clean out the food particles in the unit. You can repeat the process and get a better cleaning then too. All the scale should be off your dishes now.

Hi,

The scum, film and white residue problems have started since the reduction of phosphates in dishwasher detergents.

Here is a tip that will help you to solve the problem of films, residue, and scum in your dishwasher.

Dishwasher Residue and Film on Dishes

heatman101

./,,/.

take a good look at the two spinning washers they are easy to remove i would suspect they are clogged clean and replace.adrian,,,,

Hi,

Probably a blocked spray arm. Remove the top spray arm and check and clean all the holes as this is where the water sprays out from to clean the dishes and glasses. When they are blocked you get poor wash results.
Yes there will also be a filter in the base of the unit to clean. This needs to be done regularly to avoid food getting into the working parts of the unit.

In my experience, you probably have a clog in the spray arm/arms for the top rack. Take the arm(s) out and see if the holes in them are clogged. Rice, plastic wrappers, and glass from dishes that broke in there are the most common culprits I've seen.

clean out the food trap in the bottom inside of the dishwasher.  Also your water may not be hot enough...either select hot wash or increase your hot water heater temp. 

the problem is hard water leaving the residue. go to www.dishwasherfilter.com and get the dishwasher filtration system. it will reduce the hard minerals that leave the residue and your dishes will be clean as can be. it is very affordable and fits right under your sink.

replace the top spray arm and it should work ok again

Most dishwashers have a little filter basket in the bottom. Depending on the brand, you can slide out the bottom rack, and in the bottom underneath the sprayer (the propeller thing) there should be some sort of basket that can be removed and cleaned. You also may have some water quality issues, or some detergents will leave residue. Also, make sure most of the large food is removed before loading.