Either the outlet hose is kinked/trapped against the wall, or the pump is worn out
Put a couple of pints of water in the drum and lay the outlet hose on the floor-water should run out straight away if there is no blockage.
Take the back off and check that there are no loose pump wires. Remove the pump and check it can spin free. If everything is ok so far-then you need a new pump.
Suggest you Google "Hotpoint Aquarious Pump" There are some good deals out there as this part is common to a shedload of machines, but compare the pictures to your sample before buying, else go to www.espares.co.uk
GB in Wales
February 2013
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix dishwashers.