Hello every one
i need help about Fanuc OM-c Controller,
i'm facing the problem when i release the emergency switch, after some time magnet contractor is on,
then servo drives giving the alarm "A" and screen are showing Alarm 434 Z axis detect error. in the mean time the Z axis servo motor slightly rotate.

i tried something,

1: replace the servo Drive with good one but problem still there.
2: i exchange the command cable from JV2b to JV3b but problem exist.
3: Replace the servo Motor with Y-Axis to Z-Axis but problem is still.

I think may be parameter issues, please guide me

Thanks in advance for help.