"There are a few model years where the Motors ON Indicator at the top of the robot is tied into the Brake Circuit in such a way that a damaged cable or shorted LED can affect the entire motor harness. Worth a check!"
i don't think that is available for irb 6700. i ll cross check all the connections of motors and connectors at robot base.
what about this point "one thing that confused me that its not about a specific joint or axis, after restarting the system which ever axis i select to jog robot in that axis direction using joy stick, motion supervision and joint collision errors comes with that axis name. which means its not related to some specific axis (mechanical or electrical), even if i try to move the flex track it stops movement after few mm move and generate motion supervision error." does this make any sense?