A Signature Kitchen Suite SKSDW2401 that smells of old food or has a damp, sour odor when you open the door has trapped food and moisture somewhere in the wash path, and a systematic clean usually removes it. This is a quiet premium built-in with TrueSteam and an auto-open drying system, and none of that technology prevents food debris from collecting at the tub floor. Because the machine runs so quietly and is often used on a short cycle, residue can sit and sour between loads.
The checks in more detail
Start with the filter at the bottom of the tub. Twist it out, rinse the filters and the cup beneath under a tap with a soft brush, and look in the sump for a label, a seed or a bone. A filter packed with debris is the commonest source of odor and also spoils the wash. Then the arms and the seal. Remove the lower arm, rinse out the nozzles and wipe the door seal and the lower edge of the door, where water and soap film collect.
A thin sour film behind the door gasket smells before it looks dirty. Next the machine. Run an empty hot cycle with a dishwasher cleaner, using the TrueSteam or the Sanitize option if the model offers it, following the cleaner's label. Do not mix cleaners, and never combine bleach with other products. Check that the drain hose has a high loop under the counter or an air gap, because a hose that drops can let dirty water back into the tub from the disposer or the sink, which smells.
Change the habits too. Scrape plates but do not pre-rinse them, use the dishwasher at least once a week on a hot cycle, and leave the door slightly open after use, which the auto-open drying system does for you at the end of a cycle. If the smell persists after a clean filter, a clean tub and a hot cycle, check for water standing in the sump, which may point to a slow drain, and contact Signature Kitchen Suite support with SKSDW2401S and the serial number.
Differential
Likely causes of “LG Signature Kitchen Suite SKSDW2401 dishwasher smells bad or musty”, and how to tell them apart
- 1
A packed filter
What separates it A sour smell on opening
How to confirm Clean both filters and the cup
- 2
Film behind the door seal
What separates it The smell comes from the door edge
How to confirm Wipe the seal and door edge
- 3
A drain hose that lets water back
What separates it A sewage-like smell
How to confirm Check the high loop or air gap
- 4
Standing water in the sump
What separates it Water remains after the cycle
How to confirm Check the drain
- 5
Infrequent hot cycles
What separates it The tub smells stale
How to confirm Run a hot cleaning cycle
Before you touch a setting
Record this first — changing settings destroys the evidence
- Where the smell is strongest
- Whether the filter has been cleaned recently
- Whether water remains in the sump
- Whether the smell is sour or sewage-like
Try in this order
0 of 6 completedClean the filters
ReversibleAnd the cup beneath.
Wipe the door seal
ReversibleAnd the lower edge.
Rinse the lower arm
ReversibleAnd its nozzles.
Run a hot cleaning cycle
ReversibleWith a cleaner.
Check the drain hose
ReversibleFor a high loop.
Use it weekly
ReversibleOn a hot cycle.
Model-specific
What is true of this model and not of its siblings
- The filter
- It collects the debris that smells first.
- The seal
- A film behind the door gasket soured before it shows.
- The drain loop
- A high loop stops dirty water returning.
- Hot cycles
- They flush residue from the tub.
- Never mix cleaners
- Bleach with others is dangerous.
- Support
- Quote SKSDW2401S and the serial number.
- Parts for this problem on the SKSDW2401 (RepairClinic, 2026-09-21)
- filter, part number MDJ64544301, at $69.18; drain hose, part number AEM74333104, at $66.77; valve,check, part number MJX63511301, at $7.98; tub seal, part number 3920DD3005H, at $65.73.
Stop boundary
When this stops being a self-service repair
- !Never mix bleach with other cleaners
- !Ventilate the kitchen while cleaning
- !Call support if water stands in the sump
Evidence ledger
Sources behind this answer
Exact questions
Common questions
Why does my dishwasher smell?+
Trapped food in the filter or film behind the seal.
Do I need to pre-rinse?+
No, scrape only.
Does TrueSteam help?+
It can help in a cleaning cycle.
Why does the drain matter?+
A hose that drops lets dirty water back.
Can I mix cleaners?+
Never.
When do I call support?+
If water stands in the sump.