Display shows E10 and the interior light stays on or never turns on, sometimes accompanied by door alarm issues.

Safety: Disconnect power before working on lighting components.

• Check door switch operation: Confirm that the door switch or reed sensor correctly signals door open/close (light should toggle).
• Inspect LED module: Remove the interior light cover and check the LED board for burn marks or discoloration.
• Test LED module: If possible, test the LED with a suitable low-voltage DC supply according to Grundig specs. If it does not light, replace it.
• Check wiring: Ensure the light harness is not pinched and connectors are secure at both the light and PCB ends.
• Replace faulty parts: Install a new Grundig LED light module. If the LED is good but not receiving power, the LED driver on the main PCB may be defective and the board should be replaced.