Microwave display works and accepts time, but pressing Start does nothing; no relay click, no light, no fan.

Safety: Unplug the microwave before accessing the control panel or door switches.

• Confirm door closure: Ensure the door is fully closed and latches firmly. Try pressing the door inward while pressing Start.
• Test other functions: See if other buttons respond (clock set, timer). If only Start is unresponsive, the keypad may be faulty.
• Door switch check: If the interior light does not turn off when the door is closed, a door switch may be bad. Access and test the switches with a multimeter and replace any defective ones.
• Control board: If the keypad and door switches test good but the unit never attempts to start (no relay click), the control board relay or logic may have failed and the board should be replaced.

Because door switches are safety-critical, consider professional service if you are unsure.