How can i fix my indesit IDL40 Dishwasher?

Hi ,we have an Indesit IDL40 which has suddenly developed a fault which is shown by the first and second light flashing on and off, when i open the machine it appears the machine is failing to drain out ,i have checked the hose for kinks and crimps and also insured the hose is the correct height for discharge into the drainage system .If i tilt the machine i can manually drain it and restart it but it seems to get to a certain point then refuse to continue further with it,s programme any help would be most apprieciated, i have also cleaned out the filter, but have not taken the pump off yet to check it