@TNO_Marc also why do you want to reset E1 and E2? Are you using these values outside of reprap firmware? They are predominantly there dort the firmware to keep track of extrusion.

@norder

Probe Offsets are correct Margin about 15mm, because the limitations added by the printhead dimensions

It was the M parameter or better the P parameter i lack off, so many thanks
i suggested the M one are beginning at zero.
at least i was excepting a gap at end like 270/10.

solved then

@phaedrux Thank you very much for your kind answer.

Mystery solved: It was a bad crimp at the heater cable. Nothing to do with tuning! Checked the fuse which was perfectly fine and the output of the Board was 24.0V. Left only the bed heater as a possible problem.
Checked the resistance between both heater cables and was already worried that the heater was just broken but after removing the cable endings and checking again, there was continuity again with slight resistance. Reconnected and worked again!

Thanks again.

Epi