Machine: 2006 Doosan 2000sy with Fanuc 18i-TB control

I was running a bar feed program all day using the sub spindle as a bar puller, all was running perfect no strange sounds at all. Then the machine alarmed out and went into an E stop type mode. When I tried to move the B axis away from the part, the machine kicks off into an E stop type alarm.
I Have tried moving the B axis several times, it would only move + and - .004 then alarms out again. Then all of a sudden the B axis moves almost all the way back home while i'm using the mpg, then alarms out again. ( the axis movement sounded normal at this point ) We have removed some of the sheet metal to expose the ball screw and all looks clean and straight. When we tried to rotate the ball screw by hand it seems locked in position. I am thinking it could be a servo brake but it dose not look like there is a brake on this servo. All the other axis move smoothly at this point, it's only the B axis locking up.

Has anyone seen this type of problem?