Robot lawnmower will not start mowing; display shows E1 shortly after power‑up.

Safety first: Turn the main power switch OFF and remove the charging station power plug before working on the mower. Wear cut‑resistant gloves.

• Check emergency stop button: If your Einhell robot mower has a red stop button, press it firmly several times, then release. Ensure it is not stuck in the down position. Clean around the button with a dry brush.
• Inspect lift sensor area: Turn the mower upside down on a soft surface. Locate the lift sensor (usually a micro‑switch or tilt sensor near the front or center). Remove grass, mud, and debris with a soft brush and compressed air. Make sure the sensor lever moves freely.
• Check housing fit: Ensure the upper cover is properly latched and all screws are tight. A misaligned cover can keep the lift/tilt safety from resetting.
• Power cycle: Turn the main switch ON, place the mower on level ground, and restart. If E1 persists, disconnect the lift sensor plug from the mainboard (if accessible) and inspect for corrosion or bent pins.
• When to call a technician: If the sensor is clean and mechanically free but E1 remains, the lift sensor or mainboard is likely defective and should be tested/replaced by a service technician.