Robot mower shows E4 and stops with the wheels not turning.

Safety first: Switch the mower OFF and remove it from the lawn. Wear gloves to avoid cuts from the blades.

• Check for obstructions: Inspect both rear drive wheels and front caster(s) for stones, branches, or packed grass. Remove any debris from the wheel treads and around the axle.
• Manual rotation: Try to rotate each rear wheel by hand. They should turn with some resistance from the gearbox but not be locked. If one wheel is seized, the gearbox or motor is likely damaged.
• Inspect terrain: Ensure the mower is not being used on slopes steeper than the LandXcape model's maximum gradient. Relocate the charging station or adjust the working area to avoid steep banks.
• Check wheel motor wiring: Open the side cover or top housing (depending on model) and inspect the left and right drive motor connectors. Reseat any loose plugs.
• Test individually: Start a test run on a flat, short lawn. If E4 appears and the mower pulls to one side or one wheel does not move, replace the affected LandXcape drive motor/gearbox assembly.
• Board fault: If both wheels spin freely by hand and motors test OK but E4 persists, the main PCB current sensing circuit may be defective and should be replaced by a technician.