No display and no light indicators when powered on

The display panel connection is probably loose. The wires could also be broken where they flex whenever the top cover is opened. These are difficult to take apart but you can usually find how-to videos on youtube.

To initialize NVRAM, turn the printer power off. Remove any installed accessories (for example, a stapler/stacker). Turn the printer power on, and then hold down (SELECT button) when the memory count begins. Continue holding down until all three printer control-panel lights flash once and then remain on. This might take up to 10 seconds. Press (UP ARROW button). Press the PAUSE/RESUME button (LJ 4200/4300) or the MENU button (LJ 4250/4350). The display should show SKIP DISK LOAD. Press (UP ARROW button) until NVRAM INIT is highlighted. Press (SELECT button) the printer initializes NVRAM and then continues its power-on sequence.

Could be bad Control Panel or bad Formatter.Start with the Control Panel, it's cheaper.1st make sure the cable is attached to it.

Replace the fuser unit (they last about 75K pages in my experience)

1. Power down the printer and unplug it
2. Remove the fuser from the back side of the printer
3. Replace the fuser unit with a new one
4. Turn the printer back on

A wire is broken off of the tray 2 lift motor. It can be resoldered.

Its possible there was a voltage spike immediately preceding the power outage, thereby burning out the electronics. If you do not have a surge supressor protecting your office computers and printers, you should get one.

Well first do what joe said about checking the Plug on the Display, <Here's another solution did you also check the cables( Power Cables going to the format bd ? Sometimes you can bent those pins easily, I have seen it and ok I done it once on HP 4 plus when i first started out as a tech ? Check that ? May I asked What was the reason for replacing the Formatter board in the first Place ? were you getting an error ?

Please look on: http://www.fixyourownprinter.com/
There are much solutions of this problem listed ...

For example this (it see good):
http://www.fixyourownprinter.com/forums/printer/46157#1
HP Laser Jet 4250n by TLYNN (3/20/07 12:22 PM) reply + / -
Anybody know the error code "49. FF95 Service Error"
We can't get around this...


Firmware Error 49 by Stephen (edited 3/20/07 12:29 PM) reply + / -
It could be a bad job.

First disconnect it from your network and any PC it might be attached to.

Power cycle it, then if it goes to ready status try the built in test pages, do they work?

If the printer will go to ready status and you have a parallel cable with the proper connector, then you can try upgrading the firmware from a PC, you can also try to upgrade the firmware over the network.

More reading:

http://www.fixyourownprinter.com/search/forums?f=&q=49+4250


Re: HP Laser Jet 4250n by TLYNN (3/20/07 12:59 PM) reply + / -
Still won't go back to ready status. Turns on to the same error code....


Cold Reset HP Laser Jet 4250n by Stephen (3/20/07 1:03 PM) reply + / -
Try a cold reset, it will reset the JetDirect settings, but it's the next step.

Cold Reset:

Power off printer, wait about 5 seconds, then power it on, when asterisks start appearing on the display press and hold the check mark until all 3 lights come on solid, then use arrow keys to find cold reset and push check mark to perform the reset.



Re: HP Laser Jet 4250n by TLYNN (3/20/07 1:06 PM) reply + / -
Thank You so much for your help... but that didn't work either. Same error code showed up.


Re: HP Laser Jet 4250n by Stephen (edited 3/20/07 2:27 PM) reply + / -
Then you probably need to replace the formatter.

Do you have another printer you can swap parts with?

There is a slim chance the memory DIMM is bad, you can try it with the DIMM removed, if there is more than one DIMM you can try installing just one and then the other.
-----------------------------

A 49 error indicates that the formatter could not understand or execute an instruction within a file or cannot interface with an accessory, DIMM, or EIO device. Troubleshooting 49 errors is done through process of elimination. First determine if the printer functions in a stand-alone mode then test communications to the printer.

These errors can be divided up into two categories; the associated troubleshooting depends on the circumstance the 49 errors are occurring.

A 49 error is always followed by Hexadecimal numbers, for instance, 49.00FF. The Hex code is a memory address. Most Hex codes are not documented.


Re: HP Laser Jet 4250n by dmzcompute (3/20/07 2:26 PM) reply + / -
I do not see anywhere where the printer has been disconected from everything. If you have not done so already disconnect every cable from the printer with the exception of the power cable and turn the printer back on and see if you get the error and if not report back here for further instructions.


Re: HP Laser Jet 4250n by Stephen (3/20/07 3:28 PM) reply + / -
You might also try disabling the embedded JetDirect.

To disable the embedded LAN port

Turn the printer power off.

Power on the printer and watch for the memory count to begin.

Hold down the SELECT (Checkmark) button, when you see the memory count begin.

Continue holding down the SELECT (Checkmark) button until all three printer control-panel lights flash once and then remain on. This might take up to 10 seconds.

After the message SELECT LANGUAGE appears on the display, press the UP ARROW button or the DOWN ARROW button until EMBEDDED LAN DISABLED appears on the display

Press the SELECT (Checkmark) button. The printer then continues its power-on sequence with the embedded LAN disabled.

If this works the JetDirect built into the formatter is bad, you can either replace the formatter, or buy an JetDirect to install in an EIO slot.


Re: HP Laser Jet 4250n by Trev Pearson (3/20/07 10:08 PM) reply + / -
The only other thing to try, before spending money, is to get the network administrator to clear the print queue for that particular printer and then turn it on.

The theory being that a 'corrupt' print job is still in the system and as soon as the printer is turned on, that 'corruption' floods the network card with garbage which promptly goes 49.

If the printer comes 'ready', great. Then do a firmware upgrade. If not, then you will have to spend money on a new formatter.

Regards

Trev


Re: HP Laser Jet 4250n by roadrunner178 (6/21/07 2:09 AM) reply + / -
hi.
With a cold reset ,my problem solved.
try this as a first solution.
thank you


Re: HP Laser Jet 4250n by Anonymous (7/31/07 1:20 AM) reply + / -
Re: HP Laser Jet 4250n by Stephen (3/20/07 3:28 PM) reply + / -
You might also try disabling the embedded JetDirect.

To disable the embedded LAN port

Turn the printer power off.

Power on the printer and watch for the memory count to begin.

Hold down the SELECT (Checkmark) button, when you see the memory count begin.

Continue holding down the SELECT (Checkmark) button until all three printer control-panel lights flash once and then remain on. This might take up to 10 seconds.

After the message SELECT LANGUAGE appears on the display, press the UP ARROW button or the DOWN ARROW button until EMBEDDED LAN DISABLED appears on the display

Press the SELECT (Checkmark) button. The printer then continues its power-on sequence with the embedded LAN disabled.

If this works the JetDirect built into the formatter is bad, you can either replace the formatter, or buy an JetDirect to install in an EIO slot.

THANK YOU WERY MUCH
FROM TURKEY
ZAFER

First remove the control panel from the machine and make sure that the cable is seated well to the panel and the control board. If they are remove both cable ends and reseat them.

If the printer control panel is blank when you turn on the printer, check the following items.
1 Make sure that the printer is plugged into an active electrical outlet receptacle that delivers the
correct voltage.
2 Make sure that the on/off switch is in the on position.
3 Make sure that the fan runs briefly, which indicates that the power supply is operational.
4 Make sure that the control-panel display wire-harness is connected. See the hint in the
procedure for Top cover.
5 Remove any HP Jetdirect or other EIO cards, and then try to turn the printer on again