LD means lid is open. These machines have a proximity switch located in the left side of the top deck just beside the left side of the lid. There is a magnet fitted to the lid which operates the switch when lid is closed. Sounds like you need a new lid proximity switch fitted. The wires from the switch go into the panel & connect to the control board & pressure switch. Unless you are capable & confident enough to do it I suggest you get someone in to change the switch.
Lincoln Appliance NZ
October 2009