On a Hyster J1.8XNT Serial Number K160B05516L with manual hydraulic levers we are having a problem that the machine is sensing that someone is moving the hydraulic levers before sitting on the seat even though no one is touching the levers. The screen shows the attached photos (the four arrow icon) and no error code. the machine stope and we cannot get it to work except if we turn it off and restart again. Also if we move the levers ever so slowly with minimum input the machine might work without turning it off.

What should we look for here? is it a sensor fault or a mechanical fault? Please help.

Thanks