Robot mower will not start mowing; display shows E1 shortly after power‑on or when START is pressed.

Safety first: Remove the perimeter wire power supply plug and switch the mower OFF using the main power switch under the cover. Wear cut‑resistant gloves when handling the blades.

• Check emergency stop: On many Parkside robot mowers (e.g. PRMA series), there is a red STOP button on the top cover. Make sure it is fully released and not jammed. Press it firmly and then release.
• Inspect lift sensor area: Gently lift the mower and check that the lift sensor bracket and springs under the top shell move freely. Clean away grass, mud or debris that may be jamming the mechanism.
• Check housing fit: Ensure the top cover is properly clipped to the chassis. Misalignment can keep the lift sensor in a permanent "lifted" state.
• Inspect wiring: With power still OFF, remove the top cover (usually several Torx screws) and visually inspect the small lift sensor switch or Hall sensor and its cable to the main PCB. Look for broken wires, loose connectors or corrosion. Reseat the connector on the main control board.
• Reset and test: Reassemble, turn the main switch ON, place the mower flat on level ground and press START. If E1 persists, the lift sensor assembly is likely defective and should be replaced.

When to call a technician: If you are not comfortable opening the housing or if the lift sensor wiring is damaged at the PCB, professional service is recommended to avoid further board damage.