Hp Laserjet 2420 Dn

[rschmitt]

DISPLAY IS BLANK THOUGH THE BACKLIT IS WORKING. ENGINE TEST WORKS. NOTHING ELSE WILL. ALL THE INDICATOR LIGHTS STAY ON. REPLACED THE FORMATTER AND THE DISPLAY. NOW WHAT?

THANKS,

BOB

[BLITZKREAGG]

You might want to go after the dc controller

[JustManuals]

You might want to check the cable too. Whenever I replace a display I always replace the cable too.

HtH

Paul@justmanuals.com

[prntrfxr]

Hp Laserjet 2420 Dn

I dont remember if firmware is built into the formatter on this machine or not, but if it is a separate chip, you might consider replacing the firmware chip. A diffective chip can cause that problem sometimes. Does the board you installed have a compact flash chip?

This may be your problem as well: If the formatter you installed was a refurb, the dc controller may be confused. When you install a new board the dc controller writes to the formatter. If the formatter already has info on it, it will try to write to the dc controller. All formatters for 24XX series printers have the same part number. Unless HP has a secret PJL file to fix the problem, I'm unaware of any method of returning the printer to former condition.