Whirlpool Microwave Error Code F4E3

F4E3 indicates a failure in the hood NTC temperature sensor, which is the thermistor that monitors heat levels in the ventilation hood area of your over-the-range microwave. The control board has detected that the sensor is producing a reading outside its acceptable range, which could indicate an open circuit, short, or a sensor that has drifted out of specification. The microwave will typically stop normal operation until the fault is resolved.

It is not recommended to continue using the microwave while F4E3 is active. The hood NTC sensor is part of the appliance's overheat protection system, and operating without a functioning sensor means the control board cannot properly monitor heat levels in the hood area. This could allow the unit to overheat without triggering a protective response.

If only the hood NTC sensor needs to be replaced, parts costs are typically in the range of $15 to $50, and the repair is relatively straightforward. If the wiring harness requires repair or replacement, costs may be slightly higher. A professional appliance technician repair, including labor, generally runs in the range of $100 to $250 depending on your location and the extent of the damage.

A knowledgeable DIYer can diagnose this error by inspecting the hood NTC sensor and its wiring harness for visible damage, loose connectors, or corrosion. Using a multimeter to test the resistance of the NTC thermistor can confirm whether the sensor has failed. Replacing the sensor is a manageable repair if you are comfortable working with appliance wiring, but always unplug the microwave before beginning any inspection or repair.

Unplugging the microwave for a minute and restoring power may temporarily clear the error display, but if the underlying sensor or wiring fault still exists, the code will return. A reset is useful for confirming whether the fault is intermittent, but it does not fix the root cause. A proper repair requires diagnosing and addressing the sensor or wiring issue.