Im working on a Doosan DNM500 2012 vertical machining center , this milling machine has been a really good machine ,after a few years of having it the company added a 4th axis ( rotary table ) servo drive, power supply and all the wiring and air supply, it was installed by our local authorized Doosan installer ( AmTTech ) with no issues , just here recently the company added extra lighting , using the power from the machine and added a switch to turn it on and off, they take the 4th axis on and off as needed and at the time of the light installation the 4th axis was not being used , now when adding the 4th axis the machine throws alarms DS0300 (A) APC Alarm: need ref return, and DS0306 (A) APC Alarm: Battery voltage 0 when powering up the machine . I am not sure if it is a coincidence with the install of the light but that is the only thing that has changed. These are the things I have done to try and fix this issue: 1) Of course I replaced all the batteries on the machine the C-MOS battery behind the screen, and the APC battery on the yellow servo drive in the back, I have unplugged the external light from the machine. The alarm goes away when I unplug the 4th axis plugs from the machine. The alarm is for the (A) axis APC but I cannot find a battery just for the A axis am I missing a battery somewhere?