LG · Oven Serious
F11 — Communication error between boards
The main control board has lost communication with the display/UI board (or the cooktop board on combo ranges) for more than ~10 seconds. Cooking is blocked until the link is restored.
- Keep using it?
- Limited use only
- DIY difficulty
- Moderate
- Verified against
- lg.com ↗
How to fix it
- Power the oven off at the breaker for 60 seconds and restart.
- If F11 returns, disconnect power and pull the back panel.
- Reseat every connector on the main control board and the display board, especially the communication ribbon.
- Inspect harnesses for crushed pins or melted insulation near the cavity.
- Confirm 120 V at the line input to the main board is steady.
- If reseating does not clear it, swap the display board first (more common failure), then the main board.
Why it happens
Typical signs: F11 or F-11 on display · Touch panel unresponsive or partially lit · Oven will not start any cycle · Buttons may beep but nothing happens
- Loose ribbon or communication harness between boards Connector backed off during heat cycling or shipping/install.
- Failed display/UI board UI MCU not transmitting on the bus.
- Failed main control board Main PCB cannot receive.
- Voltage brownout or noisy power Marginal incoming voltage corrupts the bus.
Parts you may need
If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.
More LG oven codes
Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician. Verified against manufacturer documentation: lg.com.