Problem Z direction during printing

[wham]

Hello everyone,

after not having installed an auto bed leveling on my prusa I3 pro B
I have everything set direction of the motor Home position ...
when I launch an impression my auto bed does its 9 control points well
the printing starts and the pb my extrude goes down instead of going up I specify that it is reversed only during printing.
I looked on the forum it is often case of reverse printing on X and Y but I can not find Z.
so I need your lights again.

thank you

[William]

Maybe the connection of the wire of end stop is reversed. And you need to check if it is right.
If the connection is OK, you can modify the direction of Z-axis.