The F1 fault code on a Fisher & Paykel dishwasher is an indication that you have a water leak. Before calling in a professional, try to troubleshoot the problem on your own. Many times it can be something as simple as a leaky hose, a broken seal or a blocked drain hose causing the F1 error.
Unplug the dishwasher and turn off the water source to your dishwasher.
Ensure that the drawers are closed tightly. If the drawers aren't closed properly, the wash water will spill over the side and hit the sensor. Make sure you don't have anything preventing the lid from closing. Sometimes tall dishes or pans can keep the drawer from having a tight seal.
Inspect the rubber on the lid that closes down over the drawer. If the rubber seal is cracked or broken, you will need to replace this piece.
Look for junk wedged under or around the drain hole. Remove the basket and then lift off the sprayer arm. Wash away the debris on the sprayer arm by holding it under running water. Remove the filter plate located under the sprayer arm by holding the centre ring stationary and turn the outer ring in a counter-clockwise revolution, about 1/8 turn. Lift the filter plate out. Wash the filter plate in hot soapy water and then rinse. Be careful because the filter plate has sharp edges underneath.
Reinstall the filter plate. Before locking the filter plate in position, make sure the lines align with each other. Lie the filter plate flat in the drawer's base and then lock it in place. The filter plate should not move after being locked in position. Put the sprayer arm in place and then the basket.
Remove the lower drawer. Hold the front of the drawer in one hand and release the clips located on each side of the drawer with your other hand. Pull the drawer forward about 2 inches and lift. Put the drawer on its side. Exercise caution, because of the cables and wires attached.
Feel the bottom of the base for any water and soak it up with towels. The F1 sensor is attached to the bottom panel. The F1 sensor is a raised portion about one-third of the way from the left-hand side.
Inspect the hose that supplies water to the dishwasher. The connections need to be tight so no water leaks out. Also look over the water supply hose for cracks, holes or worn spots. If you find any, replace the hose with a new one.
Examine the drain hoses. If the hoses are kinked, straighten them out. If you find any worn spots or the hoses are leaking, replace them. Remove the hose and see if anything is blocking it. Go outside and use a water hose to run some water through the hose to make sure it is clear. When you reinstall the hose, make sure the connections are tight.
If your washer continues to display the F1 sign, you may need to call in a qualified repair person. Make sure to dry the dishwasher out. You can use a hairdryer to help speed up the process.