Safety first: Unplug the microwave before working on the control panel.

Step-by-step checks:

1. Power reset: Unplug for 10 minutes, then reconnect. If SE appears immediately or random beeping continues, proceed to inspection.
2. Dry the control area: If steam or liquid has recently contacted the keypad, leave the door open and allow the unit to dry for several hours. You can place a fan nearby to improve airflow (do not use heat sources).
3. Remove control panel: Remove screws securing the control panel and gently pull it forward.
4. Inspect keypad ribbon: Disconnect the flat ribbon cable from the control board. Check for corrosion, discoloration, or cracks. Clean contacts gently with isopropyl alcohol and a lint-free swab, then reseat.
5. Test behavior without keypad: With the keypad ribbon disconnected, plug in the microwave. If SE disappears, the keypad is defective. If SE remains, the control PCB is likely faulty.
6. Replace defective part: Install a new Daewoo-compatible membrane keypad or complete control panel assembly as required.

Note: Avoid pressing the keypad with sharp objects and do not use excessive cleaning liquids on the panel.

Microwave beeps continuously or randomly and displays SE (sometimes interpreted as 5E)

Possible Causes