Acer Aspire ZS600 Service Manual page 214

Remove the touch calibration tool and use two touch pens to do the multi-touch calibration,
refer to below picture to draw line within the boundary shown by the screen. The sequence
would be like upside line (left to right) → right line (upper to lower) → downside line (right to
left) → left line (lower to upper).(Refer to the sequence of 1→ 2 → 3 → 4 and the arrows in the
picture above)
4-20 Troubleshooting