The short answer
A dishwasher that will not start splits cleanly in two: either the machine has no power and the panel is dead, or the panel lights up and the machine still refuses to go. The second is far commoner and it is usually a latch or a lock. Press any button. A response of any kind — a beep, a light, a display — means the machine has power, and the fault is in what it is waiting for. On a Smeg dishwasher the cause that ranks first is control lock or delay start left engaged.
What you observe
- The panel is completely dead, with no lights and no beep — Power is not reaching the control at all.
- The machine beeps once and cancels a minute or so later — It started, waited for something, and gave up — usually water.
- NEAR MISS — the machine runs but the dishes come out dirty — That is a cleaning-performance fault and belongs on its own page.
Causes, most likely first on a Smeg dishwasher
- Control lock or delay start left engaged — A lock icon, a child lock or a delayed start swallows every press and gives no warning beyond a small symbol. It ranks first on a Smeg dishwasher because the European control aborts rather than pushing through a fault, so the sensor and lock causes surface ahead of the mechanical ones.
- Door latch not making, or the latch switch worn — The control will not energise anything until the latch tells it the door is shut, and a worn hook or a tired switch stops that signal without stopping the panel. Second on this platform: it is the single most-used moving part on the machine and it is the one thing the control refuses to start without.
- Touch panel or membrane failed — One key or a whole row stops responding while the rest of the panel works, which is the signature of a failed membrane rather than a failed board. Last, and the reason to work down the list rather than guess: it is a part fault, but a very specific one and easy to confirm before anyone is called.
Check in this order, and why
- Look for a lock or clock symbol on the display and hold the marked button — Most machines clear a lock by holding one key for a few seconds.
- Open and shut the door firmly and listen for the latch click — A soft or silent latch is the answer before anything else is tried.
- Press every key in turn and note which respond — A dead key beside live ones is a membrane, not a board.
What an owner can safely check
- Hold the key marked with a lock or a clock until the symbol clears, then press start — The manual names the key; on most machines it is the one on the far right.
About 5 min
- Close the door with deliberate pressure and press start again — Clean the latch hook and the striker plate if the click is soft.
Tools: clothAbout 5 min
- STOP HERE if the next step needs a meter on live terminals or a panel off — That is where an owner check ends and a service call begins, whatever the ranking above says.
Before you open anything
Safety
Unplug the machine or switch off its breaker before removing any panel — a capacitor can hold a charge after the power is off. Never tape, wedge or otherwise defeat the door latch to make the machine run: it is an interlock and it is there to stop the machine filling with the door open.
When to call a technician
Call once the supply, the latch and the lock are all ruled out, and call straight away if the machine trips the breaker when you press start. On a European-controlled machine, ask what the control was reporting when it stopped — it usually records why it aborted, and that shortens the visit.
Nearest pages of this class
What this page does not cover
This page is written for the Smeg dishwasher as a class, not for one family or model line. Where a family- or model-specific page exists for your unit it is linked above, it is the more specific answer, and it is the one to read first. Deliberately not here: part numbers, wiring colours, panel removal order and torque figures, all of which differ between families under the same nameplate.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
