Oven shows E13 and interior lamp does not work even though heating is normal

Safety: Switch off power and allow the oven to cool.

Replace/check lamp:

• Open the oven door and locate the lamp cover (usually glass) inside the cavity.
• Unscrew or unclip the cover and remove the lamp. Inspect the filament; if broken or blackened, replace with a Bomann-compatible high-temperature oven bulb of the same wattage and base type.
• If the new bulb does not light, check the lamp holder for signs of burning or looseness and inspect the wiring behind the cavity (access from rear panel).
• If wiring and holder are fine, the lamp control on the main control board may be defective.