LaserJet 2420d RFU Load Error

[bmsap]

We have a LaserJet 2420d that died during a power outage.  It came up with the "RFU LOAD ERROR" message, and I was able to send it the firmware by setting the thing up as "Hewlett-Packard HP USB Upgrade" and using the HP firmware update tool.

 But then it locked up with a status message of "RFU LOADED  Cycling Power".  After waiting a while, I powered it off and back on.  Now it just sits with a blank LED and all 3 status lights lit.

Is there anyway to revive this printer?  We do have another functional 2420d.
I've heard of being able to swap a part into the functional 2420d and copy the good firmware to it.

(From here: http://h30499.www3.hp.com/t5/Printers-LaserJet/hp-clj-4700-firmware-problems/m-p/2306411#M191277 )

[Pier3v]

The CLJ4700 is completly different than the lj2420 therefore that "solution" will not work.

You could try re-pushing the firmware to the printer but I think that the formatter board is toasted and needs to be replaced.