The 42C error on your Samsung Washer means the machine’s child lock function has been activated, or in rare cases, a control panel fault is preventing normal button input. This is usually a quick fix you can resolve yourself without calling a technician.

Error code 42C
Meaning Child lock is engaged, or the control panel is not registering button presses correctly
Severity Low — does not indicate a mechanical or electrical fault in most cases
Time to fix 2–10 minutes
Tools needed None

What the 42C error means

On most Samsung washing machines, 42C (sometimes shown as 4C or displayed with a padlock icon) tells you the child lock feature is turned on. This safety feature locks the control panel so buttons cannot be pressed accidentally, which is useful in homes with children but confusing if you forget it’s active.

Less commonly, this code can appear if the control board loses communication with the display panel, in which case the lock symbol may show even without the feature being intentionally activated. This is similar to how other Samsung appliance codes, such as the one covered in Samsung Washer SE Error Code: Causes and Fixes, point to a communication issue between components rather than a mechanical breakdown.

Common causes

  • Child lock button was pressed and held, either intentionally or by accident
  • Buttons on the control panel were pressed during a cycle, triggering the lock automatically
  • A power cut or reset caused the display to default to a locked state
  • Moisture or residue on the touch panel is interfering with button sensors
  • A firmware glitch is preventing the panel from registering an unlock command
  • Loose connection between the control board and display panel

How to fix the 42C error

  1. Locate the child lock button: Check your control panel for a button labelled “Child Lock” or a padlock icon, often combined with another function button.
  2. Press and hold to unlock: Hold the child lock button for 3–5 seconds until the padlock icon disappears from the display.
  3. Wipe the control panel: Dry the panel with a clean cloth in case moisture is causing false button readings, then try unlocking again.
  4. Power cycle the washer: Turn off the machine at the wall, wait 60 seconds, then turn it back on and attempt to unlock the panel again.
  5. Check the door and start again: Close the door fully, select a cycle, and confirm the lock icon stays off before pressing start.
  6. Contact Samsung support: If the padlock icon won’t clear after several attempts, the control board may need inspection — this is uncommon but possible with persistent panel faults.

FAQ

Why does my Samsung washer keep showing 42C even after I unlock it?
This usually means the child lock button is being pressed again unintentionally, or the control panel has a fault. Try wiping the panel dry and power cycling the machine before assuming a hardware issue.

Is 42C the same as a child lock symbol?
Yes, on most Samsung washer models 42C and the padlock icon refer to the same child lock function. The number code is simply how some display types represent the icon.

Can I run a wash cycle while 42C is showing?
No. While the child lock is active, the machine will not respond to the start button or cycle selection. You need to clear the lock first before the washer will run.