What FS Means
FS flags a fault in the freezer temperature sensor. LG's own troubleshooting article treats this as a component failure the control board has detected, not something a homeowner setting can fix, and says plainly that it requires a professional inspection.
Common Causes of FS
- Freezer temperature sensor has failed or lost contact
- A wiring connector to the sensor has come loose
- Main control board is misreading a normal sensor signal
🔧 One Safe Check You Can Try
There's genuinely nothing to test yourself here: unplug the refrigerator for about a minute and plug it back in once, since a one-time reset occasionally clears a sensor read glitch, and if FS returns, stop trying further resets and book service.
⚠ Why You Shouldn't Go Further Than That
- The freezer sensor sits behind the interior liner next to the evaporator, and getting to it means partially disassembling the freezer compartment - not a plug-and-play swap.
- Replacing the wrong part (sensor vs. control board) because the two produce an identical FS display wastes money without fixing the fridge.
- Running the unit for days with a genuine sensor fault lets the freezer drift out of a safe temperature range without any way to confirm it from the display.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.