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LG Microwave F1 error code

Microwave

LG microwave error code F1 means: Microwave thermistor / sensor error (often shown as F1). Some displays show this as F1. This guide covers how to reset the code, the most common causes, step-by-step troubleshooting, and replacement parts that typically resolve F1.

Safe to keep using?

Stop using

No immediate safety hazard detected, but monitor during use.

  • Unplug the appliance before inspection.
  • Microwave high-voltage components can retain lethal charge even when unplugged.
  • Do not continue using the appliance until the cause is identified.
DIY Difficulty
4 /10MODERATE

DIY difficulty: 4/10 — this repair usually requires electrical testing.

Time: 30–60 minutes
Risk: Moderate
Skill: Intermediate
Tools: Screwdriver, Adjustable pliers, Multimeter, Flashlight, Work gloves
Power disconnect required

Likely causes

Most likelyUser-serviceable issue

Many codes resolve with cleaning, resetting, or reconnecting.

Check: Power-cycle the appliance and check for obvious blockages or loose connections.

Est. cost: $0–$0

PossibleFailed component

Wear or electrical failure of an internal part.

Check: If basic checks fail, the faulty component likely needs replacement.

Est. cost: $0–$100

Repair or Replace?

DIY repair

$35–$65

Professional repair

$223–$302

Comparable replacement

$723–$977

Our recommendation

REPAIR LIKELY MAKES SENSE

REPAIR LIKELY MAKES SENSE. Professional repair ($223–$302) is well below replacement cost.

Actual repair and replacement costs vary by model, location, labor rate, and condition.

What it means

Microwave thermistor / sensor error (often shown as F1).

How to fix it

  1. Unplug the microwave and wait at least 5 minutes — high-voltage components can hold a lethal charge even when unplugged.
  2. Reset LG F1: leave power off for 5 minutes, restore power, then restart. Confirm whether F1 returns.
  3. Check the most common cause for F1: Microwave thermistor / sensor error (often shown as F1).
  4. Inspect the control pad for stuck keys, damaged membrane switches, and loose ribbon cable connections.
  5. If a reset and basic checks don't clear the code, use our lookup tool for AI-powered diagnosis or contact a qualified technician.
  6. Reassemble, restore power, and run a test cycle. If F1 returns, the faulty component likely needs replacement.

Call a pro when: Call a technician before opening the cabinet — microwave high-voltage parts can retain a lethal charge even when unplugged. Also call if you smell burning, see sparking, or the code returns after a reset.

FAQ

What does F1 error code mean on a LG microwave?

Microwave thermistor / sensor error (often shown as F1).

What does LG F1 mean?

Microwave thermistor / sensor error (often shown as F1).

How do I reset LG microwave F1?

Unplug the microwave or switch it off at the breaker for 5 minutes, then restore power and restart. A reset clears a stored F1 after a glitch, but the code will return if the underlying fault is still present.

What part do I need for LG F1?

Not always — some F1 errors are caused by user-fixable issues like clogs or unbalanced loads. Try the troubleshooting steps first.

Can I fix LG error F1 myself?

Basic resets and stuck-key checks are DIY-safe. Do not open the microwave cabinet or discharge the high-voltage capacitor yourself — call a qualified technician for internal repairs.

Do I need a replacement part for F1M?

Not always — some F1 errors are caused by user-fixable issues like clogs or unbalanced loads. Try the troubleshooting steps first.

Other LG Microwave codes

Prevent this problem next time

  • Follow manufacturer maintenance schedule
  • Address small issues before they worsen

Sources

Manufacturer meaning

Microwave thermistor / sensor error (often shown as F1).

FixApplianceCode guidance

Start with basic checks for LG F1M before ordering parts.

Source type: Part database

Source: ModelPartFinder + FixApplianceCode editorial

Last reviewed: 2026-08-24

Repair guidance is for informational purposes only. We do not guarantee that any fix will resolve your issue, and you assume all risk when following these steps. Terms & disclaimer

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