Have you checked the inlet filters on the water hoses ?
If you unscrew the water hoses from the machine, and look inside the connections on the machine, you should see the filters - they are usually a plastic "cage" supporting a gauze or fine mesh. These can be pulled out (you may need tweezers or fine nosed pliers) and washed under a running tap.
If this doesnt cure it, check that the water supplies where the hoses connect to your house plumbing are actually fully on and flowing properly, and as yours is a built in model, that when the machine is pushed back in to it's housing the water hoses are not being kinked or trapped to the point the water cant flow properly.
Otherwise, there is probably a fault with the solenoid valve(s) on the machine that controls the flow of water in to your machine.
My dishwasher runs, and it's clear that water is getting into it, but it doesn't get anything clean....
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My dishwasher runs, and it's clear that water is getting into it, but it doesn't get anything clean. I'm not sure if the bottom spinner is turning, it isn't filling with steam, and water doesn't seem to be getting off the floor of the dishwasher. Can you help me diagnose this?