Microwave will not start; display shows E01 immediately after pressing START.

Safety first: Unplug the Hansa microwave from the mains before any work. High voltage is present inside even when unplugged; do not remove the outer cabinet unless you are trained. The following steps are limited to external checks and basic switch access on models with a dedicated service flap.

• Check door closure: Ensure the door closes fully and evenly. Inspect the latch hooks on the door for cracks, warping, or obstruction (food debris, grease). Clean the latch area with a damp cloth and mild detergent, then dry thoroughly.
• Test door operation: Open and close the door several times, listening for distinct clicks from the interlock switches. If the door feels loose or does not latch firmly, the door latch or hinges may be worn.
• Inspect visible wiring (if accessible without removing cabinet): On some Hansa models, a small inner panel near the door frame can be removed to access the switch bracket. With power disconnected, remove the panel and check for loose connectors on the door switches. Reseat any loose spade terminals firmly.
• Check door switches (for qualified persons only): Using a multimeter set to continuity, test each door switch (primary and secondary) while pressing the actuator. Replace any switch that does not change state reliably.
• Reassemble and test: Refit any panels, ensure the door is aligned, plug the microwave back in, and test with a cup of water. If E01 persists, the full interlock assembly or control board may need professional diagnosis.

Warning: Do not bypass or short door switches; this is extremely dangerous and illegal in many regions.