asked Dec 2, 2013 at 1:06pm
Hp HP LaserJet 4

HP LaserJet 4 misc errors (41.2, barcode output)

I have a HP LaserJet 4 that I have serviced myself for various things in the past. It recently started doing something I hadn't seen before.

Symptoms: If it has been off for a decent period of time, when it first boots up, everything will be fine, and it will print 1-2 pages without any issues.

However, after the initial few good pages, there is a very high-pitched whining sound from the printer (some people can't hear it, but it annoys me greatly) and the printer will print one page that has horizontal lines randomly. NONE of the actual data that was supposed to print will appear on the page. This page looks like a bar code, and has no real repetition or or pattern, although the number and density of lines does seem to be a bit different depending on what I was trying to print. I can send a picture if it is useful.

After printing the defective page, the printer will occasionally give an error message (I've seen 41.2, among others that I can't recall right now) and sometimes just go straight into a "05 SELF TEST". If it goes into the self test, it hangs and will not recover. If it has the error, sometimes when I restart it will hang on the self test during boot and will not continue.

I haven't found anything exactly like this on the forum, but have already tried taking the unit apart and cleaning it, and cleaned the laser scanner assembly, with no success.

Any tips on what I can try next?

The error is a beam detect error. The noise you're describing would seem to be caused by the laser scanner motor. The horizontal lines also come from the scanner. Cleaning only applies to vertical lines. Replace the scanner assy.
by moe on Dec 2, 2013 at 2:02pm Add comment
Thanks for the quick reply! Now, do you happen to know where I can purchase that assembly? I don't see it on the FixYourOwnPrinter website, unfortunately. :)
by LeiraHoward on Dec 2, 2013 at 2:21pm Add comment
Click on my name and shoot me an email. We can provide a refurbed one at a good price.
by moe on Dec 2, 2013 at 2:26pm Add comment
Well, we have partial success. The new laser scanner assembly is installed and initially seemed to be working fine. I just printed off about 30 pages and had no repeats of the high pitched whining or error messages on the printer itself. Although I do appear to have the fan going bad (typical fan-going-bad noises) so will need to replace that shortly.

However, I did getting a bit of shadow/ghosting when printing. I ran the HPClean utility, and the blocks that are SUPPOSED to be solid black were instead partially light grey, have faint lines (or rather, areas that appear like lines that are lighter grey), and the text that appears elsewhere in the page is lighter. While trying to print some additional pages to figure out what was going on, (suspecting either bad toner or fuser), the printer jammed, and after I had removed the paper, it became stuck in "05 Self Test."

If I shut the printer off and turn it back on, it also hangs in "05 Self Test" with the ready, offline, and form feed buttons usually beginning to blink together after several minutes. If I shut the printer off and leave it off for a few minutes, when I turn it back on it MAY (or may not) go through and get to the "00 Ready" screen. But in any case, if I then send a page over from the computer to print, it starts sounding as though it will begin to print (paper tray clacks, etc.) but then goes to the "05 Self Test" without moving any paper and just hangs there.

I searched the forums here for similar issues and tried disconnecting from the computer and that had no effect.

I was able to push the button for the print test page, and got a page that looked similar to graph paper, with both vertical (evenly spaced) and horizontal (randomly spaced) lines. If I remember correctly, this test page is only SUPPOSED to have vertical lines.

Any suggestions?
by LeiraHoward on Dec 15, 2013 at 7:24pm Add comment
Update: I left the printer off all night and this morning when I turned it back on, it never left the "05 Self Test" - it eventually had the lights flash and then all lights turned off, but the message remained. Everything else from the previous post is still accurate. It is behaving much the same as it did before I replaced the scanner assembly, with the exception that I was able to print a lot of pages this time before it got stuck in the self test.

Any suggestions would be MUCH appreciated....
by LeiraHoward on Dec 16, 2013 at 7:09am Add comment
If it's printing the engine test, then that tests everything in the printer but the formatter board. If you have anything plugged into the formatter board like a jetdirect card or memory DIMMS inside, then remove them with power off. Try it again. Anything that plugs into the board can prevent the printer from warming up. Other than that, it points to the formatter board being bad. Print quality problems would point to a bad toner cartridge.
by moe on Dec 16, 2013 at 9:49am Add comment
I'm not sure if the engine printing test is being printed correctly. I printed it twice, and got two totally different looking pages. The vertical lines were the same on both, but the horizontal lines were differently spaced on each. Are there supposed to be horizontal lines at all?

by LeiraHoward on Dec 16, 2013 at 1:50pm Add comment
No. Only vertical lines. - moe
What would cause the horizontal lines? The laser scanner assembly?
by LeiraHoward on Dec 16, 2013 at 3:05pm Add comment
Also: I just turned on the printer and it went through to 00 Ready, so I printed a few things. All had issues with horizontal lines (though when printing text, these show up as horizontal WHITE lines where text SHOULD have been, as has everything since installing this refurbished laser scanner assembly) After printing about 30 pages, I got the 41.2 error. So, it sounds as though I'm still having the same issues that I did before purchasing the refurbished scanner. Any help?
by LeiraHoward on Dec 16, 2013 at 3:24pm Add comment
You never mentioned the horizontal lines were white. Can you take pics of the engine test page and a regular printed page and post them to a site like imgur.com?
by moe on Dec 16, 2013 at 3:47pm Add comment
I probably misspoke in the previous post. They aren't really white lines, they're just lines where things are printed much lighter than the line above or below (probably bad toner, but I'm not buying a new toner til all the other issues are resolved, just in case!) The lines on the engine test page are black as were the ones on the gibberish pages I had originally (before the new scanner assembly).

I'll scan in copies of the pages and email them to you later tonight, as I do not have any accounts with file uploading sites.
by LeiraHoward on Dec 16, 2013 at 4:12pm Add comment
That's why I suggested imgur. No sign up needed. Very easy to use. - moe
Thanks for the suggestion. I have created an album with the images and put text comments on each to explain what is going on. Here's the link:


Any suggestions/help would be much appreciated.

It almost seems to me as though the laser scanner works fine until it gets warmed up and then it starts acting up... but I don't know if that is a reasonable diagnosis.

by LeiraHoward on Dec 17, 2013 at 8:08am Add comment
The original problem that precipitated the laser scanner replacement was different. If you look at the lines, some were heavier and no text printed. Also there was the noise. That was the reason for my diagnosis. The only time the laser scanner is looked at by the printer electronics is when it is running to do a print. Otherwise, it isn't checked during the warmup cycle and wouldn't cause it to stay in 05 self test or revert to it. In any case, it would not go from printing lines to working OK, it would stay bad. I have only had to replace a mere handful of scanner assys. in that model in over 20 years, so that tells you how rare it is for them to fail. I have to admit that your problem is one I've never run into, so it's a bit difficult to diagnose, much less repair without being in front of it. The 05 warmup is the DC controller checking everything and communicating with the formatter board. When everything passes the tests, it tells the formatter to go to Ready. Those horizontal lines are strange. I've never seen a DC controller or formatter generate the lines. If it were here in the shop, I've got all that stuff to swap in and test. Of course you try something and since it's intermittent it might work for awhile and then go back to the same problem since you picked the wrong part to change. That's the hard part with printers that sometimes work OK and then don't. I've had lots of them where people bring the printer in, I test it in front of them and it works fine and they're astonished.
I would lean towards the DC controller, but without a high confidence level. Amazing that you suddenly got multiple problems. Very rare in that model.
by moe on Dec 17, 2013 at 10:11am Add comment
In both cases (before and after replacement), I was getting at least one page to print correctly before it went bad, but definitely the "after" laser prints MORE before going bad and does still print the underlying text with the lines (and not just a random page of lines). So it may be partially fixed... dunno, though.

I guess I'll put this on hold and continue troubleshooting after New Years - I'm using my backup printer for Christmas letters, so this can wait.

Thanks for your help so far. :)
by LeiraHoward on Dec 20, 2013 at 7:40am Add comment
Well, turns out that we are moving and I don't have the space to transport this printer anyway. So I'll be getting rid of it. Anyone want to buy it for parts? :)
by LeiraHoward on Mar 28, 2014 at 1:00pm Add comment
I've also ever met similar issue. The printer cannot print bar code images, then I try a bar code printer sdk.
The issue was solved.
by micagordon on Feb 15, 2015 at 8:06pm Add comment

Did this ever get resolved? I have a very similar problem. The printer may work fine for initial pages but after it runs for a while (about half hour or so even if not printing and just sitting on), it gets an 05 Self Test message and the ready, forms and online lights blink in unison. I should also mention that when it is turned on and working, it has a 16 Toner Low message (and I don't remember how old the toner cartridge is but I don't think it is low). The initial test page prints very nicely. I am trying to decide whether to sell it for parts or try to fix it. Any thoughts?

by wscheening on Oct 31, 2018 at 2:56pm Add comment