E11 error; door alarm may sound even when the door is closed, or interior light may not behave correctly.

Safety: Unplug the freezer before working on door switch wiring.

Steps:

• Check door seal and alignment: Ensure the door closes fully and the gasket makes uniform contact. A warped door can prevent the magnet from activating the reed switch.
• Locate door switch: On many Bosch freezers, the door switch is integrated into the cabinet frame or behind a small plastic cover near the top.
• Test switch: Remove the cover and access the switch or sensor. With a multimeter, test continuity while opening and closing the door (or moving the magnet). The switch should change state reliably.
• Inspect magnet: Some models use a magnet in the door. Verify it is present and not loose or missing.
• Replace faulty parts: If the switch or sensor does not operate correctly, replace it with a Bosch-compatible door switch or reed sensor. If the magnet is missing, install the correct replacement.

Tip: After repair, confirm that the interior light turns off and the alarm stops when the door is closed.