Printer not detected when plugged into USB port. Tried multiple PC's and cables with same result. I get an "I/O Card Not Ready" error when I print diagnostic. I also just noticed that my LCD display has gone blank. Any suggestions?

First I would recommend unplugging the machine.
Then reseat the formatter assembly.

The "I/O card not ready" is the network card which is plugged-in to the formatter. That card is for networking purposes. it will display not ready if their is not a cat5 cable plugged into it. On the first page of the configureation you should see the last 3 error codes. usually located on the left hand side half way down. if you are see 49X.XX errors you probably need to replace the formatter.



However the control panel blanking out could be several options:

First I would make sure it's not plugged into a surge protector. (HP recommends NOT to have any machine plugged into a surge protector),
Try a different outlet. if that fails that could revert back to either a bad control panel or the DC Controller. Below is a picture of the DC ControllePrinter not detected when plugged into USB port. - 2805da6.gif src="/uploads/images/2805da6.gif" alt="2805da6.gif" class="h_mi" />

Hi
Can you just tell me whats RAM size of yours . I doubt this issue occurs because of the memory problem.It can either happen in PC or Printer.
Thanks