A full cycle that ends with dry, hot dishes tells you one thing plainly: water never got into the tub. That is a different fault than a machine that won’t drain or one that leaks, and it lives in one of three spots. The inlet valve, the float, or the door latch.
First suspect: the inlet valve
The inlet valve is a solenoid-operated valve behind the lower access panel, usually front left or right, where the household line ties in. When the machine calls for water, the board powers the solenoid, the valve opens, water flows. When it fails, nothing moves and the cycle runs dry.
This is the most common cause by a wide margin. The valve fails three ways. The plunger corrodes or seizes. The solenoid coil burns open. Or the little inlet screen packs with mineral scale. That last one is more common across the Bay Area than a lot of places because the water here runs hard.
We confirm it by putting a meter on the valve during a fill. Voltage present with no water means the valve is bad. No voltage means the fault is upstream: the board, a harness connection, or one of the safety switches below. Skip that step and you risk swapping a valve that was fine.
Second: the float
Low in the tub sits a small plastic float, a dome or a cylinder. It rides up with the water level and trips a switch that shuts off the fill. If it hangs up in the raised position, from debris, buildup, or a warped float, the machine reads the tub as full and never opens the valve.
This one is fair game to check. Open the door, find the float near the bottom, lift it, and let it drop. It should move with no drag. Clean any gunk from around the base. If it was stuck and you freed it, run a test cycle.
Third: the door latch
A dishwasher will not fill if the latch is not fully engaged. The door switch is a safety interlock, and on older machines the latch wears so the door feels shut without making full contact. Push the door closed firmly and listen for a solid click. Any looseness or play, and that could be it.
The less obvious causes
Now and then the supply valve under the sink gets bumped partway closed after plumbing work, the fill hose kinks, or a relay on the control board fails. On older electromechanical machines a bad timer skips the fill step entirely. And pressure matters: most machines want at least 20 PSI at the inlet.
What is safe to try before calling
Three quick checks:
- Confirm the supply valve under the sink is all the way open.
- Lift the float and make sure it moves freely. Clean around the base if there is debris.
- Close the door and listen for a clean latch click.
Stop there. Everything past that means pulling access panels, testing live connections at the valve, or breaking the water supply in a tight cabinet. Guess wrong and you have paid for parts on the wrong fix.
Why one visit beats guessing
The full diagnosis is a single trip. We confirm supply, check the latch and float, run a fill with a meter on the valve, and tell you whether it is the valve or something upstream like the board. That order matters, because a valve swap does nothing for a board fault. On most mid-range machines an inlet valve repair is worth doing. On an older machine with other wear, ask us before we order parts.
Across the Bay Area, call (925) 999-4095 or schedule a visit. We get people on the schedule fast, often same or next day. The $75 diagnostic is credited toward the repair, and you get the price and an honest repair-or-replace call before any work starts.