C-20 Serious Moderate DIY

Samsung Oven C-20 — Oven Temperature Sensor Open/Short

Samsung Oven · Error code C-20

What C-20 Means

The oven temperature (RTD) sensor circuit is open or shorted, so the control board can't read cavity temperature. Oven will refuse to heat to protect itself.

Symptoms

  • C-20 on display, oven won't heat
  • Code appears as soon as bake is selected
  • Cavity stays cold
  • Code may pair with C-21 if reading is erratic

Common Causes

1
Failed oven temperature sensor

RTD element has gone open or shorted; should read ~1080-1100 ohms at room temp.

2
Broken or burned sensor harness

Wire from sensor to main PCB chafed or melted near oven cavity.

3
Loose connector at main PCB

Sensor plug backed out of header on the control board.

4
Failed main control board sensor circuit

PCB input stage damaged; rare but possible after a surge.

How to Fix It

  1. Power down at the breaker before working inside.
  2. Pull the oven from the wall (range) or open the rear access (wall oven) to reach the sensor.
  3. Unplug the temperature sensor connector and measure resistance — should be roughly 1080 ohms at room temperature.
  4. If resistance is open, shorted, or off by more than ~200 ohms, replace the sensor.
  5. Inspect the harness for burn marks and reseat the connector at the main PCB.
  6. If sensor and harness are good, replace the main control board.

Parts You May Need

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

More Samsung Oven Codes

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Verified against manufacturer documentation: samsung.com

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician.