asked Feb 6, 2014 at 7:38pm
Hp HP Color LaserJet 2840

Hp color laserjet 2840 issues

We have had an hp color laserjet 2840 in service for about 5 years.
Recently, it had an issue where it was stuck in "initializing" mode, or would give me a paper jam error, when there was in fact no paper stuck in it.
After trying everything i knew to do, such as cleaning the internal i could reach, and trying a few resets, i bit the bullet and found a local repair shop that works on hp printers.
The problems they found included replacing the fuser assembly, and an odd piece of cotton threading that had wound itself around some rollers (halloween decorations was my guess). They cleaned it thoroughly, and got it running again.
Everything seemed to work fine until a photo was scanned and copied.
The printout had some banding issues and wonky yellow. They assumed it was the yellow toner, since it was reporting "replace yellow".
I ordered a new yellow and replaced it (always new hp toners), but that only helped a little bit.
Any kind of test page i printed from the control panel came out nearly perfect, so that further reinforced my theory with the issue being in the scanner.
I assumed it could be an issue with the scanner bulb or assembly and began looking for replacement parts.

After a few days of testing, i have decided its not the scanner.
I reconnected it to the network and sent several images to print. Some of the images came out nearly perfect, except for any kind of photograph. Just about any kind of photo i send through it, whether via the computer or from the scanner, comes out banded and appearing low-resolution. It doesn't seem to be every kind of image, just mainly photographs.
I have checked and double checked all of the internal settings on the control panel, and checked the ones i have to use a pc to get to. Nothing seems to remedy the issue.

I'm kind of stumped, and could really use some help here.

Is it a setting i am overlooking ? Does it need firmware update? Is anything i have described sound like a part needs to be replaced, or an indication of anything going bad? Can't afford to run out an invest in a new machine,as I have recently spent $300 to get the fuser replaced and diagnosed, not to mention its just got all new toner and a drum within the last month or so.
Please help!
make sure your print driver is correct. delete and reinstall the printer. If MS Windows, what version of windows are you printing from?
by eric111 on Feb 7, 2014 at 9:12am Add comment
Both pcs networked to the printer are running the newest versions of windows 7, and had fresh drivers installed (old ones deleted as well), when i returned the 2840 to the setup. They are using the windows drivers that the os finds itself.
The results are the same regardless of printing from a computer or scanning on the flatbed and copying when not connected to the network or any computer.
by Poe_diddley on Feb 7, 2014 at 10:04pm Add comment
Can anyone help or offer suggestions? Please?????
by Poe_diddley on Feb 20, 2014 at 6:41pm Add comment
Add some more memory to 2840 and see if it helps.
There is only one memory slot left to be used.

Try to print the same file through XP system and see if it gets any difference.
There are PCL6 & PS drivers under XP but Windows 7 only PS.

Another way to try is print the file only a page once a time if it has multiple pages.
- healthup
I can look into the physical memory on the printer, thats a good suggestion i haven't considered. Maybe the repair shop coukd have accidentally left out some of the ram.

However, i don't think changing any of the drivers or computer os version will help, as it gives the bad printing whether its something thats directly scanned from the flat bed, or from a computer.

I feel like its either a physical problem with the copier, or a setting i have over looked that somehow got changed during repairs. I've considered that it might be the drum, but it doesn't do it for every image, just mostly photographs. Photos look distorted, but text and images with only linework, like outline drawings, look fine. Either from the copier or from a computer.
by Poe_diddley on Feb 21, 2014 at 4:05am Add comment
Anyone else have any ideas?
by Poe_diddley on Feb 21, 2014 at 12:26pm Add comment
Ok so i opened the side of the device where the ram can be installed, and there is nothing in the slot.
I have never opened the access port before, so i do not know, did a stick of ram come installed from the factory? I know a computer will not work at all without ram, but i do not know if this slot is for expansion only, and there is memory soldered to the board, or if someone stole the ram from our device when it was in the shop.
Please advise. I am trying to locate factory documents to see how it comes stock.
by Poe_diddley on Feb 21, 2014 at 4:58pm Add comment
Update. Still cannot determine the issue.

Replaced fuser.
Replaced transfer roller.
All toner cartridges have more than 50\% toner.
Drum is more than 50\%

It will print the demo page near perfect.
It will copy fonts and line drawings near perfect.
It will print from a computer fonts or line drawings with little to no defects.

If you attempt to copy a photo from the flatbed, or send it from a computer, it will print out a copy with banded lines going thru it, and parts of the image missing.

Color or black, the results are the same.

Can anyone offer any suggestions?
Could it be a logic board or the CPU going bad?
Please help.
by Poe_diddley on Mar 27, 2014 at 7:42pm Add comment
Change another known good formatter to see if it is the issue.
Next one will be the DC controller to try. - healthup