Using the BLtouch
With some versions of the Ender 5 a BLtouch probe is attached in these cases the unit will use it to home it’s Z axis but to ensure correct homing a start up script can used to probe the entire bed ensuring a correct level.
In Cura you can find this menu by means of the following.
Settings > Printers > Manage Printers >
Once in here click Machine Settings to entire into the start and end commands.
Your Start and end code may not look like this that is fine.
Scroll down on the Start G-code till you see a line that reads
G28 ; Home
Add the following line after
G29 ; Auto Bed Level
The End result should look like this
Once completed you can click close then you are ready to go.
From now on each time your printer goes to print it will “probe” the entire bed in a grid form and the end result will be that your printer will always level until the nozzle is changed or wears down over time.