I would recommend to upgrade the firmware to 1.05 for the latest version first. Please see attached.
And when the motor move to row 12 instead of row 8, does all moving from 1-7 is correct with the motor?
During initialization, the carriage motor shall move to the home position till it is “touch” the L shape photometric sensor in the back side that would give correct signal.
If you open the side frame house of the syringe side, you might access to the carriage motor, try to manually turn the motor to tray home position and repeat several tests to see whether self test would be success.
After switch on, the motor would calculate the steps to move from home to specific row based on the home position and encoder reading.
If it still occur after you manually turn the motor, I would guess error caused by the carriage encoder or the carriage motor.
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