Whirlpool Microwave Error Code F3 E2

The F3 E2 error code on a Whirlpool microwave indicates that the control board is detecting a signal from a warming drawer sensor circuit that is either shorted or open. Specifically, the appliance's control system is receiving a warming drawer thermistor reading that falls outside of the expected resistance range, which tells the board that the sensor has failed in one of two ways: a short circuit (resistance too low) or an open circuit (resistance too high or no continuity). The critical detail here is that the microwave is not actually equipped with a warming drawer feature, meaning no physical warming drawer sensor should exist in this unit at all.

This error almost always points to a mismatch between the installed user interface board and the main control board. The user interface board contains the software and configuration data that defines what features the appliance supports. If an incorrect user interface is installed, it may send signals or expect sensor feedback for components that were never built into the unit, such as a warming drawer thermistor. The main control interprets the absence of a sensor signal on that circuit as an open or shorted condition and triggers F3 E2.

The prescribed diagnostic approach confirms this interpretation. Pressing OFF, OFF, START to enter Diagnostics mode allows a technician to confirm the fault is active, and the corrective action is to replace the user interface board with the correct part number associated with the specific product model. No sensor replacement or wiring repair is typically required because there is no warming drawer sensor in this appliance. The fix centers entirely on installing the properly matched user interface control.