asked Nov 13, 2006 at 2:20pm
Hp HP LaserJet 4100TN


The display shows nothing but *************

I have replaced the cartridge and pulled and re-inserted the network cad and memory sticks.
Nothing seems to work. I have several of these printers and they all work flawlessly.
When you pulled the network card, did you try running the printer with the card removed?

If it is a 615N, then it is most likely your problem, and should be covered by warranty.
by Alan Mathews on Nov 13, 2006 at 2:33pm Add comment
The 4100TN didn't ship with a 615N, it likely had a 610N installed.

To troubleshoot this problem:

(power off before removing parts)

Remove JetDirect, test printer, leave card out until done troubleshooting. (If you cold reset a printer with a JetDirect installed it will reset the network configuration)

If the machine initializes with the JetDirect removed, then reinstall the JetDirect and perform a cold reset, if the card works after the reset, and the card is a 615N, then go to www.hp.com and find the download manager program, it's free, download it and upgrade the firmware of the card. If the JetDirect is a 615N there is a chance that a firmware upgrade will fix it. If it works, but is NOT a 615N you can upgrade the firmware, but the card will probably fail again within a few weeks.

Try a cold reset, power on the printer while holding down the big green button, when and if cold reset appears on the display release the button, (it seems like the message should appear somewhere between 5 and 15 seconds after you power on the machine).

Reseat firmware and memory modules, test printer. Make sure you put them in the right slots, the bottom slot must have a firmware module installed, (I don't think it hurts them to be put in the wrong slots, but the printer will be unhappy).

There should be at least 2 modules installed, Firmware in the bottom slot, memory in the next slot up, if there are modules in any other slots remove them and test printer.

Test firmware and memory in a different 4100, (you already said you have other 4100's), the firmware may be a different level in the other printers, or they may be a slightly different model, but the firmware is all interchangeable.

If you get a 68 error after putting in a different firmware module power cycle the machine once before you panic, hey if you got an error message things are improving...

If the firmware tests bad click on my name and email me, I have some extra old modules.

If the firmware and memory are good swap the formatter cage, don't try to take out the card, just swap the frame with the card in it. You can try reseating it once before swapping it, note the formatter in a 4100 needs to have firmware and memory modules installed to work.

If you still haven't fixed things, then the operator panel assembly is the next item to swap.

There is at least a 95\% chance one of those items was bad, if all those items test good in another printer then the engine board would be next on the list, but it's not very likely to cause the problem you are having.


If you need a new JetDirect I recommend the 620N, they are very stable, but be sure and buy the J7934G, some of the J7934A version cards are now failing due to manufacturing problems.

You can get a J7934G at:

by Stephen on Nov 13, 2006 at 4:08pm Add comment
Removed and re-installed the memory.

John Post
by Stephen on Feb 12, 2007 at 5:25am Add comment