Error code
tC8
Meaning
A fourth temperature sensor is reading abnormally
Moderate
What to do
Why this happens
The issue may be due to Thermistor 4 having resistance out of range (open or shorted) or a fault in the wiring harness between Thermistor 4 and PBA.
How to fix it
This one needs a professional technician to diagnose which sensor has failed and replace it.
SourceSamsung service manual / Customer Repair Guide