I cannot be sure but I think it refers to a blocked pump. My dishwasher stopped and displayed A03. I found that the pump was blocked with a few grains of rice and a small piece of potato peeling.
Make the machine electrically safe (unplug it) and turn off the water.
Take out the entire filter assembly and feel for any debris that may be blocking it.
Bail out as best you can, put the machine on its back and access the pump by removing the panel fitted at the bottom of the machine, it is held with 6 self-tapping screws. (the 3 at the front are tricky).
Carefully remove the panel and disconnect the flood switch noting the orientation of the connector.
Undo the waste pipe and blow though from the pump end to ensure it is clear.
The pump is secured with one self-tapping screw, undo this and turn it a quarter anti clockwise and lift it clear.
It has a one-way electrical connector, remove this and check the pump impeller is free. (A lollipop stick will be ideal to move it.)
Use the waste pipe to blow backwards thorough the opening that the pump drains the machine from. Any debris will be blown back into the filter sump.
Clean this debris out and reassemble in the reverse order.
Turn on the water and plug in. Try an empty cycle on the quickest setting.
Your machine should reset and then function normally.
Gerry Mooney, June 2007
