If your dishwasher is acting up, don't worry. Usually, the fix is simple and doesn't require you to call in a repairman.
Here are some common problems that you can fix yourself:
Problem: Dishes on the top rack are dirty.
Fix: You're probably loading down the bottom rack so heavily that the top rack isn't getting enough water flow. If water isn't getting to all of your dishes, not all of them are going to get clean. Use this article as your guide for proper loading technique.
Problem: There are pools of water in my dishes.
Fix: Pools of water typically come from light, plastic cups and bowls flipping over during the wash cycle. When you put light items on the rack, lean a heavier item against it to anchor it.
Problem: I used to hear water spraying really hard against my dishes, but now my dishwasher is really quiet. My dishes aren't as clean as they used to be, either.
Fix: The spouts in the sprayer arm is probably clogged with food debris. Use a toothpick to clean out the each little hole in the arm. By the way, you should do this every six months or so to prevent more clogs. Here are more tips on cleaning your dishwasher.
Problem: My glassware has little white spots all over them.
Fix: You probably have hard water, and the spots are mineral deposits. Consider installing an external hard water softening device like this one from Reverse Osmosis Revolution or buy dishwasher cleansing tablets that have a water softener ingredient.
Problem: The dishwasher overflows when I use it. I have to shut it down early, so the dishes don't make it through all of the cycles.
Fix: The filter is probably so clogged the washer can't drain properly. Look in the floor of the dishwasher. There should be a knob somewhere around the spraying arm. Twist the knob and lift out the filter. Clean it with warm, sudsy water and an old toothbrush and make sure to rinse it well. Also, make sure to scoop any food particles out of the filter hole. Screw the filter back in place and you shouldn't have any more problems.
Problem: A fountain of bubbles is coming from the dishwasher. Help!
Fix: OK, you used a bunch of dishwashing liquid instead of soap specifically for dishwashers, didn't you? No problem! Turn off your dishwasher, throw some table salt on the suds to make them dissipate and next time use dishwasher tabs or fluid cleanser. You can use dishwashing liquid, you just have to be careful. Here's how.