The short answer
Water left in the bottom of the tub is nearly always a restriction somewhere in the drain path, not a dead pump. A pump that has failed outright is silent; a pump fighting a blockage hums, strains or pulses and still leaves water behind. Listen at the end of the cycle: a hum with no water movement points at a restriction or a jam, and complete silence points at power, the control or the pump winding. On a Smeg dishwasher the cause that ranks first is filter and sump packed with soil.
What you observe
- A smell from the tub between cycles — Standing water plus trapped soil, which is the same fault seen a week later.
- Water standing in the bottom of the tub at the end of the cycle — Usually clean water above the filter, sometimes grey and smelling.
- The machine hums or pulses during the drain step but the level never falls — A pump working against a restriction, not a pump that has died.
- NEAR MISS — the machine does nothing at all and the panel is dead — That is a power or control fault and belongs on the will-not-start page.
Causes, most likely first on a Smeg dishwasher
- Filter and sump packed with soil — Food soil, labels and grease build into a mat across the fine filter until the pump can no longer pull water through it. It ranks first on a Smeg dishwasher because there is very little slack behind the panels of a compact cabinet, so anything that restricts restricts completely.
- Drain hose kinked, crushed or high-looped wrongly — The hose leaves the machine, is squashed behind the cabinet or under a plinth, and the pump cannot lift water over the loop. Second on this platform: the hose is the only part of the path that moves when the machine is fitted, pushed back or transported.
- Disposer inlet still plugged, or the disposer full — When the drain hose is tied into a food-waste disposer, the factory knockout plug has to be driven out first, and a loaded disposer blocks the same port. Last, and the reason to work down the list rather than guess: it only applies to a machine plumbed into a disposer, but when it does apply it is total.
Check in this order, and why
- Lift out the filter stack and look at the sump beneath it — It is the commonest cause and it takes a minute, so nothing else is worth doing first.
- Pull the machine forward and follow the drain hose by hand end to end — A crush point found here saves taking anything apart.
- Run the disposer with the tap on, then start a drain cycle — If the disposer clears and the machine drains, the fault was never in the machine.
What an owner can safely check
- Remove the filter stack, wash it under a hot tap and clear the sump by hand — Wear a glove — broken glass and staples collect down there.
Tools: warm water, washing-up brush, gloveAbout 20 min
- Straighten the hose, re-seat the high loop above the sump and re-clip it — Do not let the hose rest on its own weight against the cabinet back.
Tools: torchAbout 15 min
- STOP HERE — the next check means a meter, a panel, or both — The ranking above tells you what to ask for; it does not make the remaining tests owner work.
Before you open anything
Safety
Unplug the machine or switch off its breaker before removing any panel — a capacitor can hold a charge after the power is off. Bail the tub before you reach into the sump: broken glass sits in there invisibly under the water.
When to call a technician
Call once you have cleared every restriction you can reach and the level still does not fall, and call straight away if the machine trips the breaker when the drain step begins. On a European-controlled machine, ask what the control was reporting when it stopped — it usually records why it aborted, and that shortens the visit.
Nearest pages of this class
What this page does not cover
This is the generalized page for a Smeg dishwasher. It does not carry anything model-specific: no part numbers, no wiring colours, no panel sequence and no torque figures, because those differ between families sold under the same badge. Where a family- or model-level page exists it is linked above, and it is the more specific answer of the two.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
