Error Code C-21
Oven overheating - oven temperature sensor detects excessive heat or heating elements are stuck on
Moderate
Address soon - your appliance may not work properly
What This Means
Defective oven temperature sensor; Faulty DLB (Double Line Break) relay on PCB; Faulty broil heater relay on PCB; Faulty bake heater relay on PCB; Faulty convection heater relay on PCB; Disconnected or damaged harness to main PCB; Short circuit in heater wiring
How to Fix
- 1
Disconnect power and the Assy Display PCB
- 2
Check the DLB relay TB201 (1,2-3,4) — normal resistance is infinity (open) when de-energized
- 3
Check broil relay TB204 (1,2-3,4) — normal resistance is infinity when de-energized
- 4
Check bake relay TB207 (1,2-3,4) — normal resistance is infinity when de-energized
- 5
Check for damaged PCB pattern
- 6
Check connector and harness connected to CNS600 on main PCB for proper seating and damage
- 7
Measure oven sensor resistance: normal is 1080 ohms at room temperature
- 8
If sensor and harness check out, replace main PCB
This Error Applies To
Samsung NX60T8711 Series Ovens & Ranges (2023) (2023–present)
Related Error Codes
Key short — dial knob is stuck or continuously pushed
Door locking malfunction — door lock motor or switch failure
Communication error between main PCB and sub/display module, or between sub and LCD
Communication error between sub PCB and touch panel
Oven vent blocked — airflow restricted at oven vent or cover air
Ambient temperature of display PCB is excessively hot — cooling fan failure
Oven temperature sensor open circuit (resistance over 2950 ohms) or shorted (under 930 ohms)