Error code
-21°C LED LAMP
Meaning
Refrigerator cannot sense outside temperature properly
Critical
What to do
Why this happens
Potential causes include poor open circuit connections, short circuits in sensor wiring, abnormal temperatures exceeding +65°C or dropping below -50°C, and loose sensor connectors.
How to fix it
Clean connector contacts and reseat firmly; replace sensor if damaged
SourceSamsung service manual