The short answer
Standing water is a restriction, not a dead pump, in most cases. The ranking here starts with garbage disposal knockout plug, or a full disposal.
What you observe
- A few centimetres of water in the sump after every cycle — The normal picture of a restricted drain rather than a dead pump.
- The pump is audible but the level barely changes — A restriction downstream: hose, air gap or disposal.
- No pump sound at all at the end of the cycle — Points at power, a door confirmation or a jammed impeller.
- NEAR MISS — water is appearing on the floor as well — Then treat it as a leak first: the water-leak page ranks that properly.
Causes, most likely first on a SKS dishwasher
- Garbage disposal knockout plug, or a full disposal — A new disposal ships with a plug in its dishwasher inlet, and if the fitter left it in, the machine can never drain. Ranked first on a SKS dishwasher: it is the single commonest cause on a machine that has never drained since it was installed.
- Filter and sump blocked — Labels, seeds, glass chips and bone fragments all end up in the sump and all of them restrict it.
- Drain hose kinked, crushed or blocked — Grease collects at the low point of a sagging hose and narrows it over months.
- No high loop or air gap, so the machine siphons — The drain hose must rise high under the counter, or the sink water siphons back into the machine.
Check in this order, and why
- Run the disposal, then check whether the dishwasher drains — If the machine has never drained properly, ask whether the knockout plug was removed.
- Lift the filter out and look into the sump with a torch — Wear a glove: there is broken glass in more sumps than not.
- Pull the machine forward and follow the hose along its whole run — Feel for a hard, greasy section at the low point of the run.
What an owner can safely check
- Run the garbage disposal with the tap on for half a minute, then start a drain cycle on the dishwasher — If the machine has never drained since it was fitted, the disposal knockout plug is almost certainly still in place.
About 15 min
- Power off, lift out the filter, bail the standing water into a tray and clear the sump by hand with a glove and torch — Rinse the filter under a hot tap and refit it until it locks home before running anything.
Tools: glove, torch, shallow tray, jugAbout 25 min
- STOP HERE if the next step needs a panel off or a meter on live terminals — That is where the owner checks end and a service call begins, whatever the ranking says.
Before you open anything
Safety
Switch the dishwasher off at its breaker or its isolation switch before reaching into the sump — a capacitor can hold a charge after the power is off, and there is broken glass in more sumps than not. Wear a glove and use a torch rather than feeling around blind. Close the water supply valve before disturbing any hose. Do not lean on an open door: the hinge springs carry the weight of the door and a loaded rack, and a dishwasher is anchored to the worktop for that reason.
When to call a technician
Call when the filter, the sump, the hose, the disposal and the house drain are all clear and the water is still there, because what is left is the pump or its control. Call a plumber instead if the sink backs up when the machine drains. Door and hinge work on a panelled machine is a trained job: the panel weight is carried by the hinge springs and a mis-set hinge damages the cabinetry as well as the appliance.
Nearest pages of this class
What this page does not cover
This is the generalised SKS dishwasher page. A family- or model-specific page, where one exists, is linked above and is the more precise answer for your unit. Left out on purpose: part numbers, connector colours, the order panels come off in, and every torque figure — a generalised page cannot be right about any of them.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
