Clean the exterior of the dishwasher using a damp sponge and a cleanser made from mild liquid soap and warm water. Wipe away all dirt and debris with the sponge and then rinse the soap from the surface with clean water.
Open the LG dishwasher to gain access to the interior for cleaning. Slide the lower dish racks as far out of the body of the dishwasher as possible then lift the small coasters on the rear of the rack free of the washer door to remove the rack from the machine. Set the rack aside for later cleaning.
Use a nylon brush and the soap mixture to clean the rubber seal area of the dishwasher. Remove all debris from the seal then wash the area clean with a sponge. Rinse the surface with clean water.
Remove the lower spray arm from the floor of the washer by pulling it straight upwards. Examine the jet holes throughout the arm, checking for any food particles or other debris blocking the openings. Clear the openings with a soft nylon brush and water then clean the lower arm with a dishwasher cleaner and a soft cloth.
Wash around the drain of the dishwasher and the floor of the unit with a sponge and dishwashing cleaner. Check the drain for debris while washing it and dispose of any found.
Pull the upper dish rack as far forward as possible. Check the water jet holes in the upper spray arm of the dishwasher located beneath the top rack for any debris. Unscrew the nut holding the spray arm in place then clear the debris with the nylon brush, Clean the spray arm with the dishwasher cleaner and rinse with water before reattaching it back into place.
Remove the top spray arm from the roof of the unit by unhooking the hook holding the arm in place from its bracket using a screwdriver then pulling it free. Clear any clogged water jet holes then wash with the cleaner and rinse with clean water before returning it to place.
Clean the sides and top of the dishwasher with the sponge and dishwasher cleaner. Use the cleaner to clean the lower rack as well before placing it back into the dishwasher.
Fill a dishwasher-safe cup with white vinegar and place the cup in the top rack of the dishwasher. Set the dishwasher to hot and then turn on the dishwasher for a complete washing cycle. The vinegar will help sanitize the dishwasher. Remove the cup after completion and use the dishwasher as normal.