After running your dishwasher, you notice a puddle of water on the floor!
Before dismantling the door, first check to see the condition of the gasket. If the gasket is dirty or caked with detergent buildup then it may simply need to be cleaned. Using a decalcifying agent may be the best option to ensure all residue or calcium deposits are removed from the gasket surface.
There is a chance that the gasket is perfectly fine, however, if the door is misaligned it will not properly seal. Take a look at the edge of the door and make sure that it is squared up with the tub walls on both sides. If it is not aligned properly then some adjustments may need top be made to the door hinges.
If the door is properly aligned and the tub gasket is in good shape, the culprit may be a bad lower door seal. This is the hardest part to diagnose because it is not easily visible without dismantling the door. A common sign of a bad lower door seal would be where water tends to build up on the floor in the middle of the dishwasher directly below the door.
After checking for all of the possible issues listed above, the problem may be a little more extensive to repair. A cracked tub surround or a broken door may be the cause, and a visual inspection will be in necessary to properly diagnose this issue. Some indications could be where water tends to accumulate on the floor inside the dishwasher opening or between the interior door surround and the decorative outside panel or stainless steel surface. If lines are leaking simply check by wiping around the lines and fittings with a towel and see if there is any indication of water on these parts.