Hardinge Talent Turret reference

I am still struggling to get my Hardinge Talent lathe back in action. The battery failed on the Servo drive for the turret. I replaced it and now I get an alarm on the drive itself that says I need to reference the turret.

I can't seem to make anything work. The machine has a Fanuc OiTc control on it and is a 2008 model

Does anyone have a clue what needs to be done? I can't even manually index the turret. Although I can can move it by hand.


Many Thanks
Adam