Error Code C-21
Oven overheating — oven temperature exceeds 650°F (343°C) in any cooking function except self-clean
Moderate
Address soon - your appliance may not work properly
What This Means
Faulty oven temperature sensor; Faulty DLB, broil, bake, or convection heater relay on sub PCB; Disconnected or shorted harness connected to main PCB; Relay stuck closed causing continuous heating
How to Fix
- 1
Disconnect power and remove PCB Display assembly
- 2
Check DLB, Bake and Broil relay (normal resistance: infinite ohms when off)
- 3
Check for damaged PCB circuitry components
- 4
Measure oven sensor resistance (normal: 1080 ohms at room temperature)
- 5
Check harness connection at connector CNS301 on main PCB
- 6
Check whether main PCB program version is the latest
- 7
Replace main PCB if relay or circuitry is faulty
- 8
Replace or reconnect oven sensor if sensor resistance is out of spec
This Error Applies To
Samsung NX58M66 Series Ovens & Ranges
Related Error Codes
Main PCB to Touch module communication error
PCB ambient temperature too high — temperature around PCB is excessive
Shorted keypad key detected
Oven temperature sensor open (resistance over 2950 ohms) or shorted (resistance under 930 ohms)
PCB internal sensor opened (over 3900 ohms) or shorted
Door locking mechanism error — door lock motor or switch malfunction