Indramat are the drives I think and the CNC is Philips (432) ?
Are you saying the display shows 023 (zero) or O23 (oh) ?
If the display is showing an error, it would indicate the Philips CNC has output this to the screen.
Try hand wheeling all the axis to mid position and check all reference and overtravel switches, also the e-stop buttons for function and sticking.