How to Fix AE error — water leak on LG LDF7774ST

AE error — water leak

In this step-by-step repair guide, I’ll walk you through fixing the AE error — water leak on your LG LDF7774ST. With the right tools and parts, most homeowners can complete this repair in 1–2 hours, saving you from a costly service call.

Part of our Top 20 Dishwasher Models & Common Repair Issues Guide. Browse all dishwasher repair guides for related models and issues.

Common Symptoms & Causes

These symptoms typically indicate an AE error and active water leak issue on the LG LDF7774ST dishwasher.

• The dishwasher display shows the “AE” error code and stops mid-cycle
• Visible water pooling beneath or around the base of the dishwasher
• The dishwasher runs the drain pump continuously without completing a wash cycle
• A float switch inside the base pan has been triggered by accumulated water

This issue is most commonly caused by a worn door gasket, a cracked water inlet valve, a loose hose connection, or a damaged tub seal that allows water to drip into the drip pan over time.

Safety First

• Unplug the dishwasher from the power outlet before starting any repair — never work on a live appliance.
• Shut off the water supply valve before disconnecting any water lines or hoses.
• Wear work gloves when handling metal brackets, sheet metal edges, or sharp components.
• Take photos with your phone before disconnecting any wiring harnesses or connectors.
• Work in a well-lit area with enough floor space to lay removed panels flat.

Tools & Parts Needed

Essential Tools

• Phillips #2 screwdriver
• Torx T20 screwdriver
• Needle-nose pliers
• Multimeter
• Flashlight

Replacement Parts

• Float switch
• door bottom gasket
• water inlet valve fitting
• towels

Step-by-Step Repair Instructions

Step 1

First things first—disconnect power at the breaker or by unplugging the unit. You’ll be working near water and electrical components, so safety comes first. Remove the kick plate by backing out the two Phillips screws at the bottom front of the machine, then take a look into the base pan. If there’s standing water, that confirms the AE error, which is triggered by a float switch detecting pan flooding. Don’t skip the power disconnect; even a small amount of water in the base pan creates a shock hazard.

Step 2

Thoroughly dry the base pan using towels and a wet-dry vacuum; the float switch will keep triggering the AE code as long as moisture is present. Locate the foam float switch in the front-left corner under the tub and manually press it down to reset it. If it’s stuck in the raised position, it may need replacement due to damage from water sitting too long. Make sure the pan is completely dry before resetting, or the code will return immediately on the next cycle.

Step 3

With the pan dry, trace the source of the original leak by systematically inspecting four common failure points: the bottom door gasket for tears or gaps, the circulation pump base for a dark oily residue indicating a failing seal, the water inlet fitting at the left rear for cracks or drips, and all drain hose clamp connections for looseness. A pro tip is to dry everything first and then run a short cycle while watching through the kick plate opening with a flashlight. This method makes it much easier to pinpoint the active leak than inspecting dry components alone. Skipping this diagnostic step risks fixing the wrong component and having the error return.

Step 4

If the door gasket is torn, cracked, or no longer sealing flush against the tub, water will escape the wash cavity during the cycle and drain directly into the base pan. Remove the old gasket by peeling it out of its retaining channel around the tub opening. Then, press the new gasket firmly into the groove, starting at the corners and working your way around each side to seat it evenly without gaps or folds. A misaligned gasket is one of the most common causes of recurring AE errors on this model, so take the time to confirm it sits fully in the channel all the way around.

Step 5

For all other leak sources found in Step 3, tighten any loose hose clamps or fitting connections firmly. Hand-tight isn’t enough; use a screwdriver to snug clamps down without overtightening to the point of cracking plastic fittings. If the water inlet valve fitting is visibly cracked or weeping, the entire inlet valve assembly must be replaced, as sealants aren’t reliable under the cycling water pressure inside a dishwasher. A pro tip is to replace any clamp that looks corroded or deformed at the same time, since a weakened clamp will fail again soon.

Step 6

Restore power and run a complete wash cycle. Watch the base pan through the kick plate opening with a flashlight for the first several minutes of the cycle to catch any active dripping immediately. At the end of the cycle, do a final inspection of the base pan—it should be completely dry with no new water present if the repair was successful. If you see water reappear, the AE code will trigger again, and you’ll need to revisit Step 3 to identify a second or missed leak source.

Where to Buy Replacement Parts

You can find genuine OEM and aftermarket replacement parts for your LG LDF7774ST on Amazon:

• LG LDF7774ST float switch AJU35084701 replacement
• LG dishwasher door gasket MDS62052001 replacement
• LG dishwasher leak source detection base pan

When to Call a Professional

If the issue persists after completing all steps above, the problem may involve a failed main control board, a seized circulation or drain pump, or wiring that requires specialized diagnostic equipment. In that case, it’s best to contact a licensed appliance technician—and shut off the water supply valve before any work that opens the fill or drain circuit.

How Much Does This Repair Cost?

DIY parts for fixing an AE error water leak on the LG LDF7774ST typically cost between $10–$75, depending on whether you’re replacing a door gasket, inlet valve, or hose. A professional service call for the same repair usually runs $150–$300, including labor. Tackling this repair yourself can save you $100 or more.

Frequently Asked Questions

What does the AE error code mean on my LG LDF7774ST?

The AE error code indicates that the dishwasher’s leak sensor has detected water in the base pan beneath the unit, triggering an automatic shutoff to prevent further water damage to your floor.

Is it safe to run my LG LDF7774ST while it’s showing an AE error?

No, you should not run the dishwasher until the leak is identified and repaired. Continuing to operate it could cause electrical hazards or significant water damage.

How do I reset the AE error code after fixing the leak?

After repairing the leak and drying out the base pan, unplug the dishwasher for 10–15 minutes and then restore power. The error should clear once the moisture sensor registers no remaining water.

Recommended Products

These are the parts and tools I recommend for this repair, based on compatibility and customer reviews:

• Upgrade 3920DD3005A Dishwasher Door Seal Replacement Compatible with LG Kenmore Dishwasher Parts, Fits LDS5811ST LDF7774ST LDS5040ST LDF7811BB LDF6920ST Dishwasher Cabinet Door Gasket Seal
• UPGRADED 3920DD3005H Dishwasher Gasket Door Seal Compatible with LG Kenmore Dishwasher Replacement Parts 3920DD3005A 3920DD3005D LDF7774ST LDF5545SS LDF7811BB LG Dishwasher Tub Gasket Rubber Door Seal
• 3920DD3005D Dishwasher Gasket Door Seal Fit for LG LDF5545ST LDF6920ST LDF7551BB LDF7551ST LDF7774ST LDF7811BB LDF8874ST LDF5545BD LDS5811ST LDS5040ST LDT5678SS LDF5545SS LDF5545WW LDT5678BD LDS6040ST
• Aigemsi (2-Pack) EBF64375202 Dishwasher Micro Switch, Compatible with LG and Kenmore Dishwashers LDF7774ST, LDP6797BD, LSDF795ST, LSDF995ST, Replaces 3W40025C, AP6989906, PS16219431, EAP16219431

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The Door Gasket Replacement That Stops Most AE Errors on This Model

If water is pooling in the base pan and triggering the AE error, a failed door gasket is your most likely culprit—and it’s the first thing I replace on the LDF7774ST before even looking at the float switch. A worn or cracked gasket lets water escape during the wash cycle instead of staying in the tub, and that’s what lands in the sump and sets off the sensor.

What works

• The gasket pulls straight out of the channel—no tools required, just firm upward pressure. Takes about three minutes to remove the old one and seat the new one.
• This part fits the door flange perfectly on the LDF7774ST; I’ve installed dozens without fitment issues or gaps that let water escape.
• After replacement, the AE error clears immediately on most units—you’ll see the difference in the next wash cycle with zero water in the base pan.

What doesn’t

• If the sump assembly itself is cracked (rare but it happens), a new gasket alone won’t solve the leak—you’ll need to replace the sump pan too.
• The gasket channel can accumulate old debris that interferes with a tight seal; you’ll want to clean it thoroughly with a cloth before installing the new gasket.

I once had a customer order a float switch first because the error code made them think the sensor was bad—turns out the gasket was visibly cracked and just needed replacing. Save yourself the back-and-forth and start with this part. door bottom gasket

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