Diplomat built in dishwasher will not start?

Our machine would not start and was making a beep the programme light was flashing. I removed a peice of bloken glass from the pump and made sure that all pipes were free and that the pump was free to rotate. On reconnecting the machine the flashing light was still on. This is normal at the end of a cycle where upon you would hold down the start button and the light would go solid and the machine would start on closing the door. However on this occasion the light continues to flash.