The machine tool builder has set G119 bit 0 = 1 to disable PMC Ladder Display.
The PMC Ladder on a Series 0-C/D is contained on 2 EPROMs. In order to edit the PMC Ladder, you will need a FANUC PMC Ladder Edit Cassette or FAPT Ladder software, a FANUC PMC Writer or FA Writer, and the knowledge of how to use these tools.