Mesh Leveling Menu

The Activate leveling menu item, if present, is only a tool, it is like typing M420 S1 for activate and M420 S0 to deactivate mesh leveling in a terminal. Mesh leveling is also deactivated by homing, that's why it is important to write M420 S1 (or G29 A for UBL) after G28 in the start G-code script of your slicer.

The leveling system is automatically disabled after any home axis operation to prevent interference with other features like bed tramming.

Important: to enable the leveling system, a valid mesh must be loaded into memory. Verify if you have a valid mesh in memory by opening the mesh viewer.

Memory is volatile, EEPROM is permanent until it is erased or changed. Printer always uses mesh in memory. In UBL G29 P1 creates a mesh and store in memory. G29 S0 saves the current mesh in memory to slot 0 in EEPROM, G29 L0 loads a mesh from EEPROM slot 0 into memory. When you select Auto build Mesh in menu, a leveling mesh is created in memory and it is ready for be used, the printer will ask you to save the mesh into the current selected slot in the EEPROM.

If a valid mesh was previously saved in slot 0 in EEPROM, it is loaded into memory at power on. You can use that mesh activating the leveling system by using G29 A.

When a valid mesh leveling is loaded and activated, you will see the z-offset icon change as in this video: https://user-images.githubusercontent.com/2745567/210678467-308f3f9c-9c05-4ef8-8824-d4e48a072bc0.mp4