Code: F3🔧 LG Microwave

LG Microwave F3 Error Code: Touch Panel or Key Fault (How to Fix It)

Reviewed 2026-10-25 · Based on 4 manufacturer & service sources

What the code means

LG's support article "LG Microwave - Troubleshooting an F3 Error" explains that error codes on its microwave and lightwave ovens start with the letter F, and that F-3 errors can occur when there are foreign substances around the touch button panel. LG's fix is to wipe any foreign substances off the touch button panel and check again. LG also says an error can be temporary, so unplug the power cord, plug it back in and see whether the same error reappears; if it persists, call for an inspection, since other errors point to defective parts, short circuits, communication failures or overcurrent. The same wording appears in LG's help library in other countries. Appliance-repair references describe F3 the same way: Appliance Aid's LG NeoChef code table lists F-3 as a key error (clean the buttons and let them dry, then replace the key panel, then the control panel if the problem persists), and Sears PartsDirect describes F3 on LG over-the-range models as a keypad or control-panel input problem, such as a stuck key, moisture or grease, or a failing control. On over-the-range models the panel sits in the steam rising from the cooktop, which is a common way for moisture to get behind it. Other LG microwave codes mean different things: F10 or E10 on some models is a key held shorted for more than a minute, and LOC is just the control lock, not a fault.

Likely causes

Safe DIY checks

⚠ Before you start

Unplug the appliance or switch off its breaker before opening panels.

  1. Unplug the microwave (or switch off its breaker) before cleaning the panel.
  2. Wipe the touch panel and the trim around it with a soft cloth that is barely damp, then dry it completely. Don't spray cleaner straight onto the panel, since liquid can run behind it.
  3. If the microwave sits over a cooktop and F3 showed up while something was boiling, give the panel a few hours to dry out before testing again.
  4. Plug the microwave back in and check whether F3 returns. LG says the error can be temporary and a power reset is the first check.
  5. Press each pad once and note any key that feels stuck, mushy or doesn't respond. That tells a technician which part of the keypad is failing.
  6. Don't open the microwave case. Microwaves contain a high-voltage capacitor that can hold a dangerous charge even when unplugged.

🛠 When to call a pro

  • F3 comes back right after a power reset on a clean, dry panel: LG recommends an inspection by a service technician.
  • A key is visibly stuck, cracked or keeps beeping on its own: the membrane keypad or touch panel usually needs replacing.
  • The keypad has been replaced and F3 still returns: the ribbon connector or the control board needs testing.
  • You see other F codes, burning smells or the microwave runs with nothing pressed: unplug it and book service.

Parts that commonly fix it

Always match the part number to your exact model.

⚙

Touch control panel / membrane keypad

Only if cleaning, drying and a power reset don't clear F3. Match your exact model number; replacement means opening the cabinet, so leave the install to a technician.

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⚙

Microwave control board

Only after the keypad and its ribbon connector check out. Match your exact model number.

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Sources

  1. LG USA Support: LG Microwave - Troubleshooting an F3 Error (F-3 can occur with foreign substances around the touch button panel; wipe and check again; unplug and replug; call for inspection if it persists)
  2. LG Singapore help library: An F3 error is displayed (same guidance)
  3. Appliance Aid: LG Microwave Fault Code Chart (NeoChef F-3 key error: clean and dry the buttons, replace key panel, then control panel)
  4. Sears PartsDirect: LG LMV1813ST microwave/hood combo, What does F3 mean on an LG microwave (keypad or control-panel input problem)

Last reviewed 2026-10-25. Always confirm against the manual for your exact model number.