Samsung Microwave code **C-20** is associated with **temperature sensor error**. The display identifies the system or condition the control detected, but it does not by itself prove which individual part should be replaced. The useful diagnostic value of the code is the subsystem it identifies. A good repair process confirms the symptom, checks the accessible external conditions, and then follows the model-specific circuit only if the display returns. The recorded display form is **C-20**. Search normalization stores it as **C20** while preserving the characters a homeowner actually sees.
Reviewed by Ethan Mercer · Last reviewed August 17, 2026
Written by
Ethan Mercer Appliance Repair Content SpecialistPublished August 17, 2026Updated August 22, 2026Technically reviewed August 17, 2026
Content status:
Verified
Error codeC20
ApplianceMicrowave
Quick answer
Temperature sensor error.
Model compatibility: Samsung can reuse or reformat codes across series and model years, so C20 may mean something different on another appliance or generation. Confirm this against your model’s documentation and record your full model number before acting.
Plain language
What this code means
Samsung Microwave code **C-20** is associated with **temperature sensor error**. The display identifies the system or condition the control detected, but it does not by itself prove which individual part should be replaced. The useful diagnostic value of the code is the subsystem it identifies. A good repair process confirms the symptom, checks the accessible external conditions, and then follows the model-specific circuit only if the display returns. The recorded display form is **C-20**. Search normalization stores it as **C20** while preserving the characters a homeowner actually sees.
Signs
Symptoms you may notice
On affected Samsung microwave models, the control may stop or limit operation because a temperature reading is missing or implausible.
The C-20 display becomes more meaningful if heating, cooling, drying, or defrost behavior can become inconsistent.
On affected Samsung microwave models, the display can return at a similar stage each time the affected sensor is checked.
Depending on the exact model, c-20 appears and the microwave may stop or limit the function associated with temperature sensor error.
Why it happens
Possible causes
varies by model/region — cross-region baseline — Temperature sensor error
Before you call
Safe checks you can make
These are simple, non-hazardous checks only. If anything is unclear, stop and contact a technician.
With C-20 recorded, record when the code appears and whether the appliance had just heated, cooled, or defrosted.
The next non-invasive check is to confirm vents, doors, filters, and ambient conditions are normal where they affect the sensor reading.
With C-20 recorded, use the exact model manual before assuming the sensor itself is defective.
Before opening any service area, record the exact code and model number.
The next non-invasive check is to power the microwave off for 60 seconds only if Samsung's model guidance allows a reset.
Before requesting service for C-20, do not remove the outer cabinet or access internal high-voltage components.
Important safety warning. When working around a microwave that shows C-20, keep the checks external and non-invasive. Do not remove the microwave outer cabinet. High-voltage components can retain dangerous energy even after the appliance is unplugged.
Get help
When to request repair service
Once C-20 has returned after the safe checks, Persistent temperature-sensor codes usually require resistance/connection checks at the sensor, harness, and control—work best done with the model-specific service procedure. Preserve any accompanying noise, water level, temperature, or operating-stage details for the technician.
Book your repair
Seeing this code on your Samsung appliance?
Book a specialist visit for a clear estimate and approval before any repair.
Resetting can clear a temporary state, not a persistent issue. If **C-20** comes back, preserve the code and move to the safe checks or model-specific service path.
Short owner-accessible checks may be reasonable when the appliance is safe. Persistent **C-20**, worsening performance, or any electrical/water/heat hazard is a reason to stop use.
Treat **C-20** as a starting point, not a replacement instruction. Wiring, feedback signals, operating conditions, and electronic controls can mimic a failed component.
The same-looking code can be reused on another Samsung appliance family or reformatted by region/model year. Match the appliance type and exact model before applying a meaning. This page therefore keeps **Microwave C-20** separate from same-looking codes used by other Samsung appliance families.