If the tank is full but the machine cannot draw water, start at the water supply rather than assuming the pump has failed. Remove the tank and refit it firmly, checking that it sits completely in position. A poorly seated tank can prevent the tank outlet from opening correctly or stop water reaching the machine's inlet.

If a water filter is fitted, this should also be checked. A newly installed, incorrectly prepared or air-filled filter can restrict the water supply. Temporarily removing the filter and testing the machine can help separate a filter-related restriction from a wider water-flow fault.

Yes. Many removable water tanks use a spring-loaded outlet valve that remains closed when the tank is removed and opens when the tank is installed. If this valve sticks, becomes contaminated or isn't being pushed open correctly, the tank can be completely full while very little water reaches the machine.

Remove the tank and inspect the outlet area for dirt, scale or damage. The valve should move freely without remaining stuck. Also inspect the corresponding inlet area on the machine. Don't force or dismantle the valve if it isn't designed to be serviced.

Yes. A filter adds resistance to the incoming water supply, and trapped air or an incorrectly prepared filter can make that resistance significantly greater. This is particularly worth investigating if the fault appeared immediately after replacing the filter.

Remove the filter and test water delivery with the tank correctly installed. If normal flow returns, concentrate on correctly preparing or replacing the filter rather than the pump. Filters that require activation should be completely saturated and have trapped air removed before use.

The sound of the pump tells you that it is being energised, but it doesn't prove that water is reaching it. The pump may be trying to draw against an airlock, restricted filter, closed tank valve or blocked inlet.

Check the tank position and water supply first. Remove a fitted filter temporarily and try a hot-water or rinse function if your machine provides one. If the machine has recently run completely dry, the water circuit may also need to be primed before the pump can draw normally again.

Allowing the tank to run completely dry can introduce air into the inlet and pump circuit. The pump can then run without establishing enough suction to pull water from the refilled tank.

Refill and firmly refit the tank, then use the machine's priming, hot-water or rinse function where provided. Several attempts may be required to replace the trapped air with water. Avoid continuously operating a pump that remains completely dry for prolonged periods.

Don't diagnose the pump solely because no water is being delivered. First establish that water can leave the tank, the tank is correctly seated, any filter isn't restricting the supply and the system isn't airlocked.

Listen to what happens when water delivery is requested. A pump that can be heard operating but produces no water suggests a different diagnostic path from a machine where the pump remains completely silent. If the inlet supply is confirmed and priming does not restore flow, the pump or another internal hydraulic component may require further testing.