Pedal zero point adjust error: zero point adjust over size(-1.5 degree ~ 1.5 degree)

Trouble shooting procedure
Only in the pedal zero point adjustion testing function, it will cause this error. Adjust pedal positioning screw a bit.
Adjust pedal zero point position—procedure:
Connect pedal, supply power by 80V isolation transformer, turn the steel magnet, make the output of sensor voltage (voltage of C2) between 2.77~2.83V. 【Note: When you adjust pedal, you must us 80V isolation transformer supply power, the output of voltage is strong current . 】
Check the every positions of cutting to see whether it is normal.