Hologic Discovery BMD

Dear Colleagues,

I have problem in Hlogic Bone densitometer, the problem is when i do Motor AR calibration, always it failed, at movement of C-Arm CCW, before it arrives to first mechanical stop it stopped by itself and power disabled, gives Emergency stop error command,
even in the CW movement, it moves a little few degrees, then it stops.

i disconnect the Potmeter, and try to move it CW & CCW, it stopped at the same points and it gives Emergency stop errors, and the power of all movements disabled.

i disable the controller board of AR movement, and move the C-ARM manually, it stopped and disabled the power at same points.

Please if you have schematic and advance service manual, help me.

I couldn't figure out what is the root cause of the problem.

Best Regards,
Ghassan Masri
g.masri@des-carte.com