asked Dec 5, 2012 at 3:46am
Hp HP LaserJet 4L

HP Laserjet 4L - all four lights on steady error

Hi! Thanks for reading my thread, I have what I hope is a simple question regarding my HP LaserJet 4L 25pin dsub dinosaur awesome (formerly) printer.

She's "suddenly" having an issue (after a couple months of storage and shuffling around), all four lights come on which indicates the door being open or the toner cart being installed improperly.

It seems like the door sensor switch is functioning because I can hear it engage, and the printer makes an ever so faint sound as if it's running a check on the toner cartridge...

So, I'm thinking this is a toner cart electrical issue maybe? Or would it have the same issue if it were just out of toner?
Is there any way to find out without getting a new toner cart?
I suppose they're not as expensive as they used to be, and I'll certainly order one if it should get my beloved laser printer going again!
It just seems that there should have been some toner left after I last used it, as it was still printing fairly dark pages.... Also I don't think there was any sensing technology for how much toner powder was left in these sort of things so, yeah, I think my cart is not making contact with the 2 spring terminals or is just fried maybe? Of course I suppose it could be an issue with the board *gasp*...

I would so VERY much like to get this printer working again, it's always been a workhorse and delivered page after page with minimal complaints, to buy such a printer now would cost me more than I can afford - being a new parent and all..!

Thanks again if you read this far!
What you have is a Service Error. You need to push the button to get the secondary error code. That combination of lights will tell us the real problem, which is not a door open or toner cartridge problem. Report back for diagnostics.
by moe on Dec 5, 2012 at 9:22am Add comment
Actually, when you press the button, the middle 2 of the 4 lights flash off but immediately come back on, I have also tried holding the button for 5 seconds with the same result.
Thanks for your response!
by Rylan on Dec 6, 2012 at 2:05pm Add comment
I'm thinking it's a formatter board issue. You can prove it by doing an engine test which tests everything but the formatter board. If it prints a lined test page, then it'a a bad formatter. To do the engine test, open or remove the cable access panel on the rear left side of the printer. You'll see a big screw in the middle, next to the parallel connector. Below and to the right is a cutout and if you look inside, a tiny button. That's the engine test button.
by moe on Dec 6, 2012 at 2:53pm Add comment