The PLC is burned onto PROMs. A dead battery does not make the PLC vanish.
Who had the audacity to charge you for this and the parameters?
When the battery is dead, it comes up in German that the parameters are not there. At this point press clear error CE and the parameter list will come up with a question mark for the first parameter. Start typing and arrow down to the next one. Most parameters are generic. Some are not such as backlash for each axis and travel limits + and - from home for each axis.
Press the yellow button to turn the drives on. If the drives do NOT stay engaged then you have an open limit string. You need the maintenance manual or the electrical wiring diagrams. It is possible to press and HOLD the yellow button in so you can jog off the limit switch if that is where the problem is. If an axis is on a HOME switch it comes up in a block. Pressing the green button moves each axis off the home switch, one at a time with each green press. Then each green press will home an axis.
You will need the operators manual, programming manual, etc. It is impossible to give you a course or write a manual here at this forum.
George
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)