Whirlpool Microwave Error Code F6 E5

The F6 E5 error code on a Whirlpool microwave indicates that the control board has not received or retained a cavity size command. Whirlpool microwaves require the control system to know the physical cavity size in order to calibrate cooking functions, sensor cooking algorithms, and power output timing correctly. When this configuration data is absent or lost, the control cannot operate normally and displays F6 E5 to alert the technician that a required setup parameter is missing.

This error most commonly appears after the main control board has been replaced without completing the cavity size programming procedure, or after a power event causes the non-volatile memory on the control board to lose its stored configuration. It can also surface on new units where the initial programming step was skipped during assembly or installation. The condition is not related to a failed sensor or mechanical component, but strictly to a missing software configuration value stored in the control board's memory.

Diagnosis begins by pressing OFF, OFF, START to enter Diagnostics mode. The control should power up in cavity size select mode automatically when this parameter is missing. From there, the technician uses key #6 and key #3 to scroll through the available cavity size options, selects the correct size matching the unit's physical cavity, and presses START to write that value to memory. If the control board cannot retain this setting after programming, the board itself may be faulty and require replacement.