Dishwasher Won't Start: Causes and How to Fix It
Updated · from manufacturer service documentation
A dishwasher that won't start almost always comes down to the door not being fully closed, a Control Lock feature left on, or a stuck button — check these before suspecting a real fault. Service documentation across brands treats a door-open condition and a stuck/held button as the two most common non-mechanical causes.
What Causes a Dishwasher Not to Start
| Cause | Likelihood | DIY difficulty | Related part |
|---|---|---|---|
| Door not fully closed within the required window after pressing Start | Most common | Easy — close door properly and retry | — |
| Control Lock (child lock) feature left active | Common | Easy — deactivate Control Lock | — |
| A button stuck or held down continuously | Common | Easy — check for a stuck key | Control panel |
| Door lock switch faulty | Less common | Moderate — check switch | Door lock switch |
| Main PBA (control board) fault | Rare | Pro repair | Main PBA |
How to Fix a Dishwasher That Won't Start, Step by Step
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Close the door within the expected window
On LG's platform, you must either press Start and close the door within four seconds, or close the door first and then press Start — if the timing doesn't line up, an alert sounds and nothing starts.
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Check whether Control Lock is active
LG's Control Lock feature locks all buttons except Power during a cycle, which prevents starting a new one — deactivate it (press and hold the documented button combination) before trying to start a cycle.
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Check for a stuck or continuously pressed button
Samsung's documentation flags this directly: if a button is pressed continuously for an extended period (10–30 seconds depending on model), the control logs a Button Error and the panel stops responding normally — inspect the panel for anything physically holding a key down.
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Check that the door is actually closing and latching
Samsung's diagnostic lists a faulty door lock switch as a possible cause when the door-open warning persists even with the door visibly shut.
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If none of the above resolves it, the main control board may be at fault
This is a job for a technician.
Where This Comes From
Cross-referenced from LG's LDF5545ST/LDF6810/LDT7808 dishwasher service manuals (Start/Control Lock behavior) and Samsung's DW80F600 series service documentation (Button Error and Door open warning diagnostics). Both independently point to door-closing timing and stuck controls as the leading non-mechanical causes.
See also: Dishwasher not draining, Dishwasher not cleaning.
Frequently Asked Questions
Why does my dishwasher beep instead of starting?
On LG models, this usually means the Start-to-door-close timing wasn't met — you have about four seconds between pressing Start and closing the door (or close the door first, then press Start).
What is Control Lock, and could it be stopping my dishwasher from starting?
Yes — Control Lock disables all buttons except Power to prevent settings from changing mid-cycle. If it's active, deactivate it before trying to start a new cycle.
Could a stuck button be the reason my dishwasher won't respond?
Yes — if a button is held or stuck for an extended period, the control treats it as a Button Error and the panel may stop responding as expected until it's cleared.
Is a door-related won't-start issue the same as a "door open" error code?
Related — if the door isn't fully closed, or the door lock switch itself has failed, the control can't confirm the door is secure and won't begin the cycle.
Based on the LG service documentation for the LDF5545ST/LDF6810/LDT7808 dishwasher series and the Samsung service documentation for the DW80F600 series. Last updated: .