Oven interior light not working, or an error/warning related to the lamp circuit appears on some models.

Safety first: Switch off power at the mains. Even lamp circuits can be at full mains voltage.

• Replace the bulb: Remove the glass lamp cover inside the cavity (usually unscrews). Replace the bulb with the exact type and wattage specified by Grundig (often a high-temperature halogen or LED).
• Inspect lamp holder: Check for heat damage, discoloration, or loose contacts in the lamp holder. If the holder is brittle or burnt, replace it.
• Check wiring: From the rear of the oven, inspect the lamp wiring harness for signs of overheating or cuts. Repair or replace as needed.
• Control board output: If a known-good bulb and holder still do not light, the lamp relay or triac on the main PCB may have failed. Board repair or replacement is required.

Note: Use only high-temperature-rated bulbs designed for oven use; standard bulbs will fail quickly and may shatter.