How to fix Homing Fail/Alarm 8/Alarm 9?

Please open LaserGRBL or LightBurn to and connect machine to confirm the controller bit as following figure: (or Type "$i" into the command box).

If it appears: MKS DLC32, it is 32-bit, otherwise it is 8-bit.

Method 1
Connect LE400PRO to the computer and import the configuration file:

Steps in LaserGRBL:

Click “Grbl Configuration”, then click “Import”.

Choose the file “LE400PRO8Bit NC” or “LE400PRO 32Bit NC”（According to your machine to choose）, and click “Close”.

After the import is successful, try homing again.

save as a file → LE400PRO 8Bit NC.nc    LE400PRO 32Bit NC.nc

*Please refer to the picture in next pages.

Method 2
Please check belt to confirm whether the laser module is parallel to the X-axis bar. If not parallel, re-tighten the belt.

Method 3
Please check whether the opening direction of the limit switch is correct, if not, it needs to be adjusted. You can refer to the following video:

If there is no opening direction error in the limit switch, you can try to install the limit switches of the X-axis and Y-axis in exchange.

Method 4
Flash the firmware
Please refer to the attachment file “How to flashing firmware - LE400PRO” for the details.