LG oven F21 error code
F21 means door lock error. The door lock did not engage when a program was started, so the oven will not begin..
Often fixable at home · Fault type: Electrical/hardware
Safe checks, in order of likelihood
- Re-close the door firmly and clear anything blocking the latch.
- Clean around the latch — grease and debris stop engagement.
- Power-cycle and retry.
Call a professional when…
If F21 persists with a clean closed door, the lock or its switch is replaced. If the code returns after these checks, book a qualified engineer.
Parts usually involved
- LG oven door lock assembly.