Oven interior light does not turn on, or stays on permanently regardless of door position.

Safety first: Switch off power at the breaker. Lamps and holders can be live even when the oven is off.

• Replace the lamp: Remove the glass lamp cover inside the cavity (usually twists off). Replace the bulb with a Miele-approved high-temperature oven lamp of the same wattage and base type. Restore power and test.
• Check door switch/contact: Many Miele ovens use a door contact switch or reed sensor. Inspect the switch near the door frame. Test continuity while opening and closing the door. Replace if it does not change state reliably.
• Inspect lamp holder and wiring: Look for heat damage or loose connections at the lamp holder. Repair or replace as needed.
• Light stuck on: If the light remains on with the door closed and the switch tests good, the light relay on the control board may be stuck. Control board replacement is usually required.

Use only high-temperature-rated lamps; standard bulbs will fail quickly.