Occasionally my poor dishwasher suffers from bad breath. It hits me when I open the door and almost knocks me down. This is when I realise it needs a little TLC too and so I go to work.
First thing you need to do is clean the filters. Yes they do need to be cleaned regularly by you. In my dishwasher the filter is in three parts: a basket type of thing that then sits in a mesh basket and the stainless steel top filter. All three parts can be lifted out for cleaning. Fill a sink with some hot water and washing soda. Take the filters out, scrape off the gunk and soak in the hot water. Scrub with an old toothbrush if you need to. Rinse in hot water and put them back into place.
To help with odours and clean the inside of your dishwasher you can add 2 tablespoons of bicarb soda to the detergent dispenser. Pour ½ cup white vinegar into the bottom and run the econo or light cycle. Your dishwasher will be sparkling inside.
Once the cycle has finished, rinse a cloth in white vinegar and use this to clean around seals and the edge of the door, wiping off any gunk or grime that has built up. Pay special attention to the fiddly spots around the hinges, they can be really disgusting.
Do this twice a year and your dishwasher will always smell sweet and be sparkling clean inside.