Whirlpool Microwave E24 Error Code - Causes & Fix

Whirlpool Microwave E24 Error Code — What It Means

The E24 error code on Whirlpool over-the-range microwaves indicates a problem in the thermal sensing circuit. While Whirlpool’s public documentation lists E24 as a recognized fault code, the exact definition is not published in consumer materials. Based on closely related codes in the same family, E24 most likely signals either an open circuit, short circuit, or out-of-range reading from the thermal sensor (thermistor) that monitors cavity or magnetron temperature. This sensor protects the microwave from overheating by reporting temperature data to the control board.

When the control board detects a sensor reading outside normal parameters or loses communication with the thermistor entirely, it halts operation and displays E24. The fault can stem from a failed sensor, damaged wiring, poor harness connections, or a defective control board input circuit. Less commonly, an actual overheating event or blocked vent may trigger the sensor into fault mode.

Jump to Fix

Common Causes

• Failed thermal sensor or thermistor The temperature sensor itself develops an internal open or short, sending incorrect or no signal to the control board.
• Damaged or disconnected sensor wiring harness Wires between the sensor and control board can break, fray, or pull loose from vibration or heat exposure over time.
• Poor harness connector contact Oxidized, bent, or loose pins at the sensor or board connector prevent reliable electrical continuity.
• Faulty appliance control board The main control board’s sensor input circuit may fail even when the sensor and wiring test normal.
• Blocked ventilation or actual overheating Restricted airflow or a genuine thermal event can push the sensor reading beyond the control board’s safe threshold.
• Control board solder joint failure Cold or cracked solder joints at the thermistor input on the board create intermittent or permanent open circuits.

Step-by-Step Fix

1. Disconnect power at the circuit breaker and wait two minutes for high-voltage capacitors to discharge before opening any panels.
2. Reset the microwave by restoring power and observing whether E24 returns immediately or only during heating cycles.
3. Access the thermal sensor by removing the outer cabinet or top grille, then locate the thermistor mounted near the magnetron or on the cavity wall.
4. Inspect the wiring harness from sensor to control board for visible breaks, heat discoloration, loose connectors, or corroded terminals.
5. Test sensor continuity by unplugging the thermistor connector and measuring resistance across the sensor leads, then compare to your model’s specification sheet if available.
6. Replace the thermal sensor if resistance is infinite (open), near zero (short), or the sensor shows physical damage or intermittent readings.
7. Replace the control board if the sensor and all wiring test normal but the E24 fault persists after reconnection and a full power cycle.
8. Clear the fault by disconnecting power for 30 seconds, then run a short cook cycle to verify the code does not reappear.

Parts Often Needed

When to Call a Pro

Call a qualified appliance technician if you are uncomfortable working around high-voltage microwave components, cannot safely access the sensor or control board, or lack a multimeter and the skills to interpret resistance and continuity readings. Professional help is also recommended if you replace the sensor and harness yet the E24 code returns, since control board diagnosis and replacement require precise part matching and sometimes involve reprogramming or calibration. Any situation involving visible arcing, burning odors, or repeated nuisance tripping of your home circuit breaker warrants immediate professional evaluation to rule out magnetron or high-voltage circuit faults that may not be evident from the error code alone.