Error Code FRIDGE-SENSOR
Refrigerator compartment temperature sensor is disconnected or dead
Moderate
Address soon - your appliance may not work properly
Also displayed as: R blinks
What This Means
Loose or disconnected CN20 connector; Failed R-sensor thermistor (502AT) — open or short; Damaged wiring between sensor and CN20; Poor solder joint at R210 (IC01 MICOM pin 5) on Main PCB
What actually causes this:
The sensor measuring fridge compartment temperature has failed, so the control board cannot regulate cooling properly.
First Thing to Check
Check that the small white wire harness at the back wall of the fresh food section is plugged in and undamaged.
Parts Involved
How to Fix
- 1
Verify CN20 connector is fully seated on Main PCB
- 2
Measure voltage between CN20 pin 9 (W/YEL) and pin 11 — must be 0.6V to 4.6V
- 3
Disconnect CN20 and measure resistance between pin 9 and pin 11; compare to DATA1 temperature table
- 4
0 Ω = short (replace sensor); ∞ Ω = open wire or sensor (replace sensor/trace wire)
- 5
If sensor resistance is correct, check PCB solder at R210
This Error Applies To
Samsung RF28T5 Series Refrigerators (2020) (2020–present)
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