Beneath the tub of an LG dishwasher is a shallow pan with a float switch in it. If water reaches that pan, from a leak or from overfilling, the float rises and the control stops the cycle and shows AE, or on some models EI or FE. LG lists all three under leakage and overfilling. Of all the codes an LG dishwasher can display, this is the one to take most seriously, because water is standing beside the machine's pump motor and wiring, and because the cause is often still leaking.
Power and Water Off Before Anything Else
Switch the dishwasher off at its breaker before you open the door, reach under the sink or touch anything wet, because the base pan you are about to deal with holds water next to live components. Then close the water supply valve to the dishwasher under the sink, so that if the fault is the inlet valve or a split hose the water stops arriving. Put towels along the front of the machine. Only then open the door and look.
What You Can See From the Front
Foam is the first thing to look for. Hand dish soap, a rinse-aid spill or a detergent not meant for dishwashers produces suds that climb the tub and escape at the door seal and vent, and the run-off ends up in the base. A tall pot or a tray leaning against the door can lift the door slightly or deflect a spray arm straight at the seal. Run a finger around the door gasket for food debris, a tear or a section pulled out of its channel. Check the machine is level: a dishwasher that leans forward brings water against the door seal at every fill. Look under the sink for drips at the supply connection and at the drain hose.
Do Not Tilt the Dishwasher
Do not lean or tip the machine to pour the water out of the base pan. A built-in dishwasher is fixed to the counter, plumbed with lines cut to length, and tilting it strains those connections and can bring water into contact with the wiring you have just isolated. Do not remove the toe-kick panel to reach into the base pan either. The pan is emptied by a technician with the machine isolated, and the point of emptying it is to see where the next drop comes from.
What the Technician Is Looking For
With the base dry, the machine is refilled and watched. Common sources on LG dishwashers are the inlet valve or its connection, the sump seal around the pump, a cracked or perished hose inside the cabinet, the door seal at the lower corners, and a tub that has developed a crack at a rack-wheel mount. Overfilling with no leak points at the inlet valve not closing or the water level sensor misreading, which LG lists separately as PE.
The Damage Is Not Only to the Dishwasher
Water that leaves the base pan runs under the cabinet floor and along the subfloor, where it swells particleboard and lifts flooring long before anyone sees it. If you have noticed a soft spot in the kitchen floor near the machine, a smell, or a dark line at the toe-kick, say so when you book, because it changes what the visit needs to include. Whether any of that is covered by a household policy is a question for the policy and the insurer, not for a repair site.
Until the Visit
Leave the breaker off and the water valve closed. Do not run the dishwasher again to see whether the code has cleared; the float is telling you the base pan is wet, and another fill adds to it. Book an LG dishwasher repair with the code exactly as displayed, the model number from the plate on the door edge, and what you found at the seal and under the sink.