Samsung Ovens & Ranges2019–present

Error Code C-21

Oven heating over - Temperature rising too fast or sensor shorted

Moderate

Address soon - your appliance may not work properly

What This Means

Oven sensor shorted; Defective heater relay; Heater continuously on; Damaged main PCB pattern

How to Fix

  1. 1

    Disconnect power and open back cover

  2. 2

    Disconnect sensor harness from control

  3. 3

    Measure sensor resistance (should read 25-1000 ohms at room temp)

  4. 4

    Check broil, bake, and convection heaters for resistance

  5. 5

    Check if DLB of sub PCB, Broil, Bake and Convection heater relays working normally

  6. 6

    Check for disconnection of harness linked with main PCB

  7. 7

    Measure resistance of oven sensor connector on main PCB

  8. 8

    Replace main PCB if relay damaged or pattern cracked

This Error Applies To

Samsung NE59J3420S Series Ovens & Ranges (2019) (2019–present)

Service manual exact match: NE59*432***Service manual exact match: NE59J3420SSService manual exact match: NE59M3420SSService manual exact match: NE59J3421Service manual exact match: NE59J3421SS

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