mypros+
Error code reference

Whirlpool Refrigerator Error Code RC & DEFROST SENSOR

Both the refrigerator compartment and defrost thermistor sensors have failed.

Whirlpool codesWhirlpool refrigerator codes

Both the refrigerator compartment and defrost thermistor sensors have failed.

First step from the service manual

Enter service diagnostics mode; thermistors are automatically tested after Heater Off (Step 4).

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

MyPros+ Max

Get the full diagnostic procedure for RC & DEFROST SENSOR.

  • Step-by-step tests with expected resistance, voltage, and continuity values
  • Wiring diagram references and connector pinouts from the OEM service manual
  • Verified part numbers when replacement is required
Get the full procedure

$29/month · Cancel anytime · Or $9.95 3-day pass

What RC & DEFROST SENSOR means on a Whirlpool refrigerator

The RC & DEFROST SENSOR error code on a Whirlpool refrigerator indicates a simultaneous failure of two separate thermistor circuits: the refrigerator compartment (RC) thermistor and the defrost thermistor. These are negative temperature coefficient (NTC) sensors that change resistance in response to temperature changes, allowing the control board to monitor compartment and evaporator temperatures in real time. When both sensors report readings outside acceptable parameters at the same time, the control board flags this combined fault code.

Because two independent sensors have failed together, the root cause is often not the sensors themselves but rather a shared component or wiring path. A faulty main control board, a damaged wiring harness, or a connector problem in the circuit common to both sensors are frequent culprits. In some cases, a freezing event or moisture intrusion can degrade multiple sensor connections simultaneously, causing both circuits to read open or shorted conditions at the same time.

Diagnosing this fault requires entering service diagnostics mode. Thermistors are automatically tested following the Heater Off step (Step 4) in the diagnostic sequence. This structured test allows the technician to confirm whether one or both sensors are truly defective or whether the fault originates upstream in the wiring or control board. Replacing sensors without completing this sequence risks misdiagnosis and unnecessary parts replacement.

Source: manufacturer service documentation.

Common causes of RC & DEFROST SENSOR

  1. 01

    Faulty main control board

    Part replacement

    When two unrelated sensors fail simultaneously, the control board is often the shared failure point. A damaged or failing board may incorrectly read both thermistor circuits as faulted even when the sensors themselves are functional.

  2. 02

    Damaged or corroded wiring harness

    Wiring / connection

    A wiring harness that routes to both thermistors can develop breaks, shorts, or corrosion at connectors, causing both circuits to fail at the same time. Inspect all connectors and wiring paths serving the RC and defrost thermistors for physical damage or moisture intrusion.

  3. 03

    Failed refrigerator compartment thermistor

    Part replacement

    The RC thermistor itself may have an open or shorted circuit, producing an out-of-range resistance reading. This can be confirmed during the Step 4 thermistor test in service diagnostics mode.

  4. 04

    Failed defrost thermistor

    Part replacement

    The defrost thermistor monitors the evaporator coil temperature and can fail due to age, ice buildup, or repeated thermal cycling. A defective defrost thermistor will register an abnormal resistance value during the diagnostic test sequence.

  5. 05

    Loose or disconnected connector at sensor terminals

    Wiring / connection

    Connectors at either thermistor can work loose over time due to vibration or thermal expansion, causing intermittent or complete signal loss. Reseating all connectors in the sensor circuit should be checked before replacing any parts.

See the test procedure for each cause

Frequently asked questions about RC & DEFROST SENSOR

What does RC & DEFROST SENSOR mean on a Whirlpool refrigerator?
This error code means both the refrigerator compartment thermistor and the defrost thermistor have been detected as failed by the control board. These sensors monitor temperatures inside the fresh food section and at the evaporator coil. When both fail together, the refrigerator cannot regulate cooling or defrost cycles accurately. The fault is confirmed through service diagnostics, specifically during the thermistor test that runs automatically after the Heater Off step.
Can I fix the RC & DEFROST SENSOR error myself on a Whirlpool refrigerator?
A knowledgeable DIYer can inspect wiring connectors and reseat any loose connections, which sometimes resolves the fault without part replacement. However, properly diagnosing whether the sensors, the wiring harness, or the control board is at fault requires entering service diagnostics mode and interpreting the thermistor test results. Replacing parts without completing the diagnostic sequence often leads to misdiagnosis. If you are not comfortable working with appliance control systems, a professional technician is recommended.
Is it safe to keep using my refrigerator when the RC & DEFROST SENSOR error is active?
Continued use is not recommended once this error is active. Without functioning temperature sensors, the control board cannot accurately manage cooling or defrost cycles, which can result in inconsistent temperatures and potential food spoilage. Frost may also accumulate on the evaporator coil if the defrost system is impaired. The issue should be diagnosed and repaired as soon as possible to protect stored food and prevent further damage.
How much does it cost to repair the RC & DEFROST SENSOR error on a Whirlpool refrigerator?
Repair costs depend on what component has actually failed. Thermistor sensors are relatively inexpensive, typically in the range of $15 to $50 per sensor in parts. A replacement main control board, if that turns out to be the root cause, can range from $100 to $300 or more in parts alone. Adding professional labor, total repair costs can range from $150 to $500 depending on the diagnosis and parts required.
Will resetting my Whirlpool refrigerator clear the RC & DEFROST SENSOR error?
A simple power reset may temporarily clear the error code from the display, but it will not resolve the underlying fault. If both thermistor circuits are genuinely defective or if there is a wiring or control board issue, the code will return once the refrigerator resumes normal operation. The correct approach is to run the service diagnostics thermistor test to identify and repair the actual cause before attempting to clear the fault.

Related Whirlpool refrigerator codes

All Whirlpool refrigerator codes
View all 218 Whirlpool refrigerator codes

78,000+ service manuals · 160,000+ error codes · 55+ brands

Get Started

$29/month · Cancel anytime · Or $9.95 3-day pass