How to Clean the Drain Pump Filter on a LG WM3900HWA Washer — Step-by-Step Instructions
Step-by-step instructions for the LG WM3900HWA (front-load washer, direct drive). Parts and access points can differ slightly by production year — the steps below cover the common layout for this platform, and the model notes flag its quirks.
Unplug the washer first. The trap may hold a surprising amount of water — go slow with the cap and let it drain into the pan in stages.
Tools
- Shallow pan or baking dish
- Towels
- Flashlight
Parts
- None — this is maintenance
Step by step
-
1 Find the access door
On nearly every front-loader there’s a small rectangular door or kick-panel at the bottom front corner. Pop it open with a flat screwdriver or coin.
-
2 Drain the water first
Most machines hide a small rubber drain hose next to the filter cap. Pull it out, aim it into your shallow pan, and remove its plug. No hose? Unscrew the filter cap a quarter-turn and let water seep out in stages.
-
3 Unscrew the filter
Turn the cap counterclockwise and pull the coin trap straight out. Expect gunk: lint mats, coins, hair pins, guitar picks, and at least one sock over the machine’s lifetime.
-
4 Clean everything
Rinse the filter under hot water, scrub with an old toothbrush, and shine a flashlight into the pump housing — spin the impeller with a finger to make sure nothing is jammed behind it.
-
5 Reinstall and test
Screw the filter back in snugly (crooked threads leak), replug the drain hose, close the door, and run a short cycle to confirm draining and no drips.
LG WM3900HWA notes & error codes
The direct-drive motor is warrantied for 10 years — if a shop blames the motor, make sure they check the hall sensor and wiring first, and ask about LG’s parts warranty before paying for one.
| Code | What it means |
|---|---|
| OE | Drain error — filter, pump, or hose |
| IE | Fill error — taps, screens, inlet valve |
| LE | Locked motor / hall sensor |
| UE / uE | Unbalanced load (uE = machine self-correcting) |
| dE | Door open / lock fault |
| tE | Thermistor (heater temp sensor) fault |
Full details for this machine — common problems, causes, and costs — are in the LG WM3900HWA repair guide. The general version of these instructions is here.
If the filter is clean but the washer still won’t drain — or the pump hums or grinds with the filter out — the pump itself is likely failing, and diagnosing pumps vs control faults is quick work for a tech. If you'd rather skip it entirely, find a washer repair pro near you →
What this repair costs professionally
Sources
Where the safety, regulatory and warranty claims on this page come from. Repair costs are our own figures based on Arizona market rates and OEM parts pricing.
- Refrigerator Limited Warranty (PDF) LG Electronics U.S.A. Compressor and sealed-system warranty terms, including which years cover labour.
Find a washer repair pro near you.
Browse verified independent appliance repair companies by city — ratings, hours, and phone numbers, no middleman.