It's not the battery, it's mad that it was disconnected. Check this post that I copied down and now can't find the thread to give proper credit:
Procedure:
1. Press I/O button
1a. (EDIT) I think you have to press I/O F key then the right arrow, I do it so often to change the write parameter that it is just habit and I can't remember)
2. Press right Arrow key
3. Press "Version"
4. Press "1" then <enter> (Parameter write enable)
5. Press 'I/O Menu" F key
(Takes you back to the very first menu screen of the I/O menu, should see a list of options for the F keys vertically on the screen)
6. Type -9999 and <enter>
7. Bottom right of the screen you will see "Reset Addt'l Axis" (next to last F key)
8. Press that F key
9. Cursor to the first box beside of "A" (or B) axis label depending on how the tilt/rotary is mounted
10. Press "2" <enter> (reset encoder counter)
WAIT until the 2 disappears
11. Move cursor back to that box and press "1" then <enter> (set axis display to 0)
Follow Steps 9-11 for "B" axis (or C axis, depending on how they are on the table)
Press <rst> key (reset)
Note: This just resets the encoders to wherever the table is currently at to be Zero. To properly set up the axis, you would of course tram in the A (or B - tilt) axis and reset the encoder again. - Same for the rotary. You can use the second box over from the A, B or C label to actually tell it a dimension to set the axis to when you do the 1 <enter> thing. i.e. if you tram the tilt axis in at -90° then you would enter -90.000 in the second box over before you did the 1 <enter> of the above procedure. You can also just do a 1 <enter> if you haven't changed motors/encoders and the encoder counts that are displayed match pretty closely
