Step-by-Step DIY Fix Guide
- SAFETY: Disconnect power at the circuit breaker.
- Reset by restoring power after 60 seconds and testing.
- If F38 returns, call an LG-authorized technician. Board-to-board communication faults require specialist diagnostic tools.
If the airflow problem comes back
- If airflow still seems weak after the basic checks, the fan path or a deeper obstruction becomes more likely.
- F38 persists after a 60-second power reset
What This Error Means
Error F38 on your LG oven means: The main control board and the inverter board (which controls the induction cooktop or convection motor on applicable models) have lost communication. Induction cooking or convection may be unavailable. The range's self-diagnostic system has detected this condition.
The most frequent cause is inverter board failure. Work through the causes and fix steps below in order — many LG oven errors are resolved without a service call.
LG's official guidance classifies F38 as a technician-only fault. A 60-second power reset is the only DIY step — if the code returns, contact LG Support at 1-800-243-0000.
Electronic communication and fan faults require professional diagnosis. A power reset resolves transient faults. If the code returns after a reset, a physical component has failed.
Most Likely Cause by Symptom
The LG oven may stop, pause, or refuse to complete the cycle normally.
Likely cause: Inverter board failure
Check first: SAFETY: Disconnect power at the circuit breaker.
The warning may return immediately because the appliance is detecting an internal fault.
Likely cause: Main control board communication circuit failure
Check first: Reset by restoring power after 60 seconds and testing.
Common Causes
- Inverter board failure
- Main control board communication circuit failure
- Wiring harness fault between the main board and the inverter board
- Power surge corrupting board communication
What Not to Do
- Do not continue using the induction cooktop with F38 active — incomplete communication between boards can cause unpredictable heating behavior
Model and Display Variation Notes
Model-family notes
- LG oven display wording and code formats can vary by series.
- If your model behaves differently, check the owner manual before trying any deeper maintenance step.
Display and panel differences
- Panel wording can vary by series, so confirm the exact code pattern before buying parts.
Parts, Tools and Service Options
Service option
LG service visit if the warning returns after the basic checks are complete.
Manual and model check
Check your exact model and manual before ordering any LG oven parts.
Common parts
- Inverter board if inverter has failed ($80–$200)
- Main control board if main board communication has failed ($100–$250)
- Wiring harness if connector fault is confirmed ($20–$50)
This section stays service-first because the page points more strongly toward support or professional repair than a routine parts purchase.
When Not to Keep Troubleshooting
F38 persists after a 60-second power reset
How to Prevent It Recurring
- Use a surge protector on the range outlet — power surges are a leading cause of inverter board communication faults on LG induction ranges
Related Error Codes
F11
The oven's display/control panel and the main control board have lost communication. The two boards cannot exchange data, so the oven cannot accept commands or display status correctly.
F42
The oven has detected that the incoming supply voltage is either too high or too low. Electric ranges require a stable 240V supply (two 120V legs) — a missing or weak leg will trigger F42.
Extra notes
- This page is based on LG support material and stays conservative where model-specific guidance may vary.
- The goal is to help you identify safe first checks before you move into parts, service, or model-specific manual lookup.
Source and model notes
Last reviewed: 2026-04-08
Based on: Based on LG support material and edited into consumer-safe guidance for the exact code family on this page.
Model coverage note: LG oven code meanings can vary by series, control panel, and model family, so use this page as a safe starting point rather than a replacement for the model-specific manual.
Important: FixThisError is an independent guide, not the manufacturer. Use your model-specific manual when the panel wording or behavior differs.
Always disconnect power before inspecting appliances. If unsure, contact a licensed appliance technician.