What does LG Dishwasher Not Cleaning Dishes - Causes & Fix mean?

Most often caused by a clogged filter restricting water flow. Remove and clean the filter under running water, then reinstall.

How do I fix LG Dishwasher Not Cleaning Dishes - Causes & Fix?

Follow the step-by-step diagnosis below. The most likely fix is identified by checking power, sensor resistance, and control-board signals in order — using a multimeter and the part numbers documented in the parts reference table.

Can I keep running the equipment with this fault active?

Generally no. Faults on Appliance units are emitted when a sensor, safety, or control circuit is outside its operating envelope. Running through an active fault risks compressor, heater, or control-board damage. Diagnose and clear the fault first.

What part is most commonly replaced for LG Dishwasher Not Cleaning Dishes - Causes & Fix?

The most frequently replaced parts for LG Dishwasher Not Cleaning Dishes - Causes & Fix are listed in the Parts Reference section of this guide with OEM part numbers and typical price ranges. Check the table for direct replacements.

Is LG Dishwasher Not Cleaning Dishes - Causes & Fix a DIY repair or do I need a technician?

Sensor swaps, fan motor replacements, and condenser cleaning are typical DIY-level repairs. Anything involving refrigerant, gas, or high-voltage (>240V) work requires a licensed technician for both safety and code-compliance reasons.

LG Dishwasher Not Cleaning Dishes - Causes & Fix

LG Dishwasher Not Cleaning Dishes — What’s Happening

When an LG dishwasher leaves dishes dirty, LG support identifies the main culprits as a dirty filter, improper dish loading, or interior residue buildup from food and grease. This is a symptom complaint, not an error code, and the machine usually runs a full cycle but fails to remove food or leaves a film on dishes.

Service technicians understand this as a problem in the wash-water path. Common root causes include restricted filtration or spray, low water delivery to the tub, insufficient water temperature, or a weak circulation pump that cannot generate enough spray pressure to clean properly.

Jump to Fix

Most Likely Causes

Clogged or improperly seated filter Trapped food debris in the filter assembly reduces circulation and wash water quality, leaving dishes dirty even when the cycle completes.
Improper dish loading Overlapping dishes, blocked spray arm nozzles, or tightly packed utensils prevent water from reaching all surfaces and cause poor cleaning.
Blocked spray arm holes Plugged spray nozzles or physical obstruction of the arm prevents proper spray coverage and leaves dishes unwashed in certain zones.
Interior buildup of grease and scale Residue on the tub walls, door seals, and plumbing reduces wash effectiveness and can redeposit soil onto clean dishes.
Low inlet water pressure or kinked supply hose The inlet valve requires 20 to 120 PSI to operate correctly, and inadequate supply reduces fill volume and weakens circulation.
Low water temperature Water below approximately 120°F does not dissolve detergent fully and cannot cut grease, resulting in poor wash performance.
Failing wash motor or circulation pump A weak or failing pump cannot generate adequate spray pressure, so dishes stay dirty even when filters are clean and loading is correct.

How to Diagnose and Fix

Confirm the symptom by checking whether dishes are truly dirty versus spotted, and verify that detergent is dissolving and rinse aid is filled if spotting is present.
Inspect dish loading in both racks to make sure items are not touching, not blocking spray arm rotation, and are arranged according to the rack pattern recommended by LG.
Remove the lower rack, lift out the filter assembly, and clean all screens and the fine mesh under running water, soaking and scrubbing if debris is heavy, then reinstall securely.
Remove the upper and lower spray arms, flush all nozzle holes with water, clear any obstructions, verify the arms spin freely by hand, and replace any arm that is cracked or warped.
Run a machine-clean or tub-clean cycle using citric acid or a dishwasher cleaner to remove grease, scale, and food residue from internal surfaces.
Check that the supply valve is fully open, the inlet hose is not kinked, and water pressure at the valve is adequate (20 to 120 PSI range), then run a short cycle to confirm normal fill volume.
If cleaning is still poor and fill volume is normal, observe spray arm rotation and spray force during the wash phase to evaluate whether the wash motor is circulating water properly.
If the wash pump is suspect, verify the motor is receiving proper voltage during the wash phase and check winding resistance per your model’s service data, then replace the circulation pump assembly if it fails electrical testing or produces weak spray.

Parts You Might Need

Part	Notes
LG dishwasher filter assembly	Amazon \| Includes fine mesh and coarse screen, model-specific
LG dishwasher spray arm (upper or lower)	Amazon \| Verify part number by model before ordering
LG dishwasher wash motor / circulation pump	Amazon \| Required when pump fails electrical tests or produces weak spray

If your appliance also shows a code on the display, these match this problem:

When to Call a Pro

Call a qualified appliance technician if dishes remain dirty after you have cleaned the filter and spray arms, verified proper loading and detergent use, run a tub-clean cycle, and confirmed adequate water supply. Diagnosis of a failing wash motor or circulation pump requires electrical testing and access to model-specific service data, and replacement involves disconnecting plumbing and wiring inside the tub. A pro can test voltage, measure pump resistance, evaluate spray pressure, and safely replace the motor assembly or related components if the wash system has failed.