Problem with mesh bed leveling on modified M3D Promega

[TheNetStriker]

I'm trying to run the mesh bed leveling on a modified M3D Promega with leadscrews for the bed instead of the standard belts. I followed the manual from dehidding on Thingyverse:
https://www.thingiverse.com/thing:3601545

So far everything seems to work, but I'm getting a strange result when running the mesh bed leveling. All the points are way above the grid:

What could cause this problem and how can I solve this?

[3ddevil]

@TheNetStriker I believe this is just in reference to your G30 command and how Z=0 was set in the first place. Now that you have the map, the absolute height is probably not relevant as long as you are testing G0 Z0 at a few points and it seems to be in the right place.

[Phaedrux]

Can you post your homing files and config.g?
Are you homing with a probe using G30?

[TheNetStriker]

On a second try the level was already better. I now reconfigured the z homing so it is probing against the z probe and not the end switch. Now the height map levels are quite good.