Lg Oven Error F9

⚡ Quick Answer: The LG oven error F9 indicates a malfunction in the oven temperature sensor, leading to erratic temperature readings and failure to heat. Specifically... ⚠️ Difficulty Varies

What Does Error F9 Mean?

The LG oven error F9 indicates a malfunction in the oven temperature sensor, leading to erratic temperature readings and failure to heat. Specifically, this error occurs when the oven fails to reach 150°F within five minutes of preheating, which may result from a faulty relay board, defective temperature sensor, or issues with the heating elements or igniter. Users may notice that the oven stops preheating shortly after starting or fails to achieve expected temperatures.

Common Symptoms:

  • Oven stops preheating and displays F9 shortly after starting preheat
  • Oven fails to reach expected temperatures in reasonable time
  • Heating elements do not seem to energize
  • Igniter (gas) does not glow sufficiently or ignition fails

Possible Causes

  • Temperature preheat failure (control detects insufficient heat rise) (medium)
  • Faulty relay board / control board preventing proper power to heating circuit (medium)
  • Defective temperature sensor (electric models) (medium)
  • Faulty igniter (gas models) (medium)
  • Damaged heating element (electric models) (medium)
  • Faulty thermal fuse or wiring issues (low)

How to Fix Error F9

DIY Fix Power reset and error clear

  1. Press Clear/Off to reset the control panel.
  2. Disconnect the oven from power — unplug or switch off its circuit breaker.
  3. Wait 5 minutes to allow internal electronics to reset.
  4. Restore power and attempt preheating again.

DIY Fix Basic checks before calling service

  1. For gas ovens, ensure the gas supply is turned ON.
  2. Visually check that the igniter glows when preheating (for gas models).
  3. Look for obvious damage to heating elements or sensors through the oven interior.

Technician Only Inspect and test heating components

  1. Disconnect mains power and remove access panels.
  2. Test heating elements (electric) or igniter (gas) for continuity and proper operation.
  3. Test the oven temperature sensor resistance to verify it’s within spec.
  4. Inspect the relay board and control board for faults.
  5. Check internal wiring harnesses for damage or loose connections.

Parts needed: Heating element, Igniter (gas), Temperature sensor (RTD), Relay board, Control board, Thermal fuse

🛑 When to Call a Pro:
  • If the error persists after a proper power reset and basic checks
  • If the user is uncomfortable with internal diagnostics
  • If multiple components show signs of failure or wiring damage is present

Technical Specifications

wattage N/A
component Oven Temperature Sensor
resistance 1000-1100 ohms
part_number LG 6323B61000B
voltage_rating 120V AC

Common Questions

What does F9 error mean on LG oven?

The F9 error indicates a malfunction in the temperature sensor, causing heating issues.

Can I fix LG oven F9 error myself?

Yes, you can try a power reset and check the igniter or heating elements before calling a technician.

How much does it cost to fix F9 error?

Repair costs for the F9 error can range from $100 to $450+, depending on parts and labor.

When should I call a technician for F9?

Call a technician if the error persists after basic checks or if you're uncomfortable with diagnostics.

Sources & References

Data last verified: 2026-01-11

User Comments (0)

Share your experience or solution below.

Be the first to comment!