RJ3 Controller not turning on

  • Hey,

    I have a Fanuc RJ3 controller, that I am unable to get to work.

    I have very little experience so please excuse me if I have made some stupid mistakes.


    Main board serial: A16B-3200-0330

    Side panel serial: A20B-2100-0470

    The PIL led on the PSU turns green when I flip the breaker on (Picture 1).

    The controller has a broken mode selector switch, so the CRT7 connector that connects the selector with the board is disconnected (Picture 2).

    All breakers seem to be in working order.

    Does the mode selector need to be wired for the controller to turn on or is the problem somewhere else?

    Picture 1:


    Picture 2:


    Picture 3:


    Thank you for your time!

  • AD
  • You don't need the TP mode switch connected to get the system to power up.

    You might have an issue in the ON/OFF circuit. On an R-J3 the components included would be the switches, cables to the panel board, panel board, cable to main board, main board, backplane and the power supply. It routes through nearly every controller component.

    TBOP2 needs a jumper between terminals 3 and 4. This is your connection for an external OFF button. It needs to be shorted for the controller to power up. Your photo shows no TBOP2 connector in place.

    If you still have issues after that, on the PSU short pins A1, A2 and A3 together on CP4 to simulate pressing the ON button. If the controller boots up then you know one of the other components mentioned is an issue.

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