(1)pressure chamber blockage,(2) faulty pressure switch, before you buy a switch try this,With power OFF
remove lid pressure switch is the large round thing with a small CLEAR PLASTIC PIPE running down to the drum remove the small pipe from beneath switch BLOW DOWN THE PIPE YOU SHOULD HEAR BUBBLES (if you can't pipe is blocked with soap powder residue, grease, etc ,trace the pipe down to bottom of machine(prepare for spillage) remove pipe and clear blockage (you will see the hole is very small) reassemble and try if it still overfills change the pressure switch (NOTE) how the wires are connected first before removing switch. Buy a new switch by taking the old one with you as a pattern. reassemble and TRY.
wirecutterman, January 2008