I'm having a problem with an Index lathe. The lathe is German built and has an old Siemens System 8 control.The control suffered serious corruption when the main isolator started to arc. A new isolator was fitted and the memory areas were cleaned out using cancel 0,1,2 etc. All the neccessary data was re-loaded and the machine seemed to be OK. However when the part program is ran the data lock light comes on and the machine refuses to move.All other functions such as turret index and zero return are OK.The problem appears to be related to either G59 (work shift) or the control not reading the tool offsets. Any help would be appreciated.