The answer, before the detail
Standing water in a Big Chill DWT dishwasher at the end of a cycle is usually a blockage rather than a failed pump, and it is usually in the two places you can reach: the filter and sump inside, and the drain hose route under the sink. On this family the filter leads. A small amount of water always sitting in the sump, by contrast, is normal and is not what this page is about. Settle the build before the ranking applies: these models divide on a machine plumbed in under the counter.
What you observe on these models
- Water backing up into the sink when the machine drains — A disposer fitted recently is the first thing to suspect here.
- A smell from the tub between cycles — Water that is not leaving is water that is standing, and standing water in a warm tub smells.
- A partial drain that leaves a shallow layer — This is the version that is easiest to fix and easiest to ignore.
- NEAR MISS — a small amount that never goes — Judge by what covers the tub floor, not by the recess.
Causes, ranked for the DWT build
- The filter and sump are blocked — On a grinder build it drops down the list, which is why establishing the build comes first. Labels, seeds and broken glass all end up here.
- The drain hose is kinked, blocked or has lost its high loop — It ranks high because it is common, invisible and free to fix. Look for the flat spot where something has been pressing on it.
- The disposer knockout plug or the air gap is blocking the outlet — It also rises whenever a disposer has recently been replaced. A new installation that has never drained points here before anywhere else.
- The drain pump is jammed or has failed — Last, because every cause above it is reachable without tools and this one is not. A hum with no drain, after the filter and hose are clear, is what is left.
The order that finds it fastest
- Scoop the water out and look at the sump — Use a jug and a cloth, and watch for glass.
- Inspect the filter and the sump recess — This is the commonest single cause on filter builds and the fastest to clear.
- Check the hose route, loop and any kinks — Look for a flat spot, a bin pressed against it, or a loop that has dropped since the last time anything was moved under there.
- Check the disposer connection or the air gap — An air gap comes apart by hand and blocks with the same debris as the filter.
Before you open anything
Safety
Switch the machine off at its breaker before reaching behind the kick plate or the door panel — water and mains wiring share the same small space in a dishwasher, and a capacitor can hold a charge after the power is off. Leave the door latch and its switch exactly as they are: the machine is meant to stop the moment the door opens. Broken glass in the sump is a hand injury waiting to happen; use a torch and a cloth, never bare fingers.
Where the owner job ends
Call when the filter, the hose route and the waste connection are all clear and the tub still holds water — that leaves the pump and the parts under the tub. Call sooner if you can hear the pump hum without moving water, or if there is glass in the sump: a fragment in the impeller is a common cause and a bad thing to fish for by hand.
Other faults covered for the DWT models
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
