PRIO - 063 Bad I/O asg: Rack 1 slot 1

  • I have an RJ2 420 I that is giving the Prio-063 bad I/O asg: rack 1 slot 1 error. None of my outputs for auxillary equipment are working since the error and there are no lights on the plc. This robot cell had been working fine. After sitting over a weekend we came in to the stated error and nothing functioning.

  • AD
  • I know it makes the most sense for the error you're seeing to be the reason your line is down, but I actually have that error permanently displayed on one of our LR Mates, and the robot and cell run fine. The error has been showing for (apparently) as long as we've had the machine- ~8 years. And does not negatively impact anything. I'd probably check other issues on yours as well.

  • ST I understand what you are saying but this line ran great until we got this error and now when you look at the outputs on the pendant screen they are still written on the screen but there is no longer a designation of on or off is just shows an asterisk and you can not manually turn them on or off any longer.

  • rumblefish, thank you it is an A controller I only have two A controllers, all the rest are B's so I am not as familiar with it. Rack 1 slot 1 is the CPU board, Slot 2 is the psu board which has a cable going to the plc to power it but doesn' t. Both boards Led's show normal operation.

  • Rack 1 Slot 1 is not the CPU.

    On Fanuc robots Rack 1 refers the the physical IO rack. Rack 1 Slot 1 would be the first physical IO card.


    Since you said your outputs are not working then it is obvious that you have lost communication with the IO card. Rumblefish provided the answer above, I am just hoping to clarify it for you.


    You could have a bad IO cable, IO module, or IO card. Or simply it could have come slightly unplugged.

  • Recently saw this error on an R-J2 when someone had removed a Model 'A' input card in slot 1 and installed an output card. Because the auto config variable was True, it had automatically changed the I/O configuration to the new cards but the I/O assignments did not match. Put the I/O modules back in their correct slots, fixed the configuration to match the assignments and cycled power. To keep this from happening again, then changed variable $IO_AUTO_CFG to False and did a Cold Start (hold the Fault Reset while powering on) to enable the variable change. Changed the $IO_AUTO_CFG variable to False on their other R-J2 robots too.

  • These modules made me work too hard. It works fine when I install the new module. But after a while it starts to make that mistake. Whether you check all your power connections or do the entire configuration again, it doesn't matter. With this given error the robot can work only when you want to give manual movement you need to do a double reset. In this module "I/O Link" port in the continuation of the door integration after a while the communication signal voltage begins to leak. Fanuc good that this integrated market type can be found in the integrated module starts working normally when you change used. As someone who has tried a lot of different configurations and connections, that's my view. Isolating the voltage using a relay at the module inputs and outputs can take a while but then it fails again.

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