E18 error, oven interior light does not work and some functions may be disabled.

Safety first: Switch off power at the mains before changing the lamp or touching the lamp holder.

Steps to check:

• Replace lamp: Remove the glass cover inside the oven and replace the bulb with a high-temperature oven lamp of the correct wattage and fitting.
• Inspect lamp holder: Check for heat damage or corrosion on the lamp holder contacts.
• Wiring check: If the new lamp does not work, inspect the wiring from the lamp holder to the control board.
• Control board: If wiring and lamp holder are good, the light relay on the control board may have failed and require board replacement.