asked Aug 15, 2006 at 10:40am
Hp HP Color LaserJet 2550

HP LaserJet 2550n Carousel moves but misaligned

I have a 2550 with a bad case of cyan slobber that I decided to give a good cleaning to. I removed all of the trays, fuser assembly, imaging drum and toner cartridges and then blew it out with compressed air.

Everything went well until I went to install the cartridges again where I found that they were misaligned. After some frustration, I figured out that I could trick the printer by opening the cover at just the right instant so it would stop the carosuel at the right spot to let me install my cartriges.

Despite my creativity, the carousel seems to still be out of alignment and nothing I have done has caused it to find home again. As a result of being misaligned, it seems like it doesn't find the cartridges and it has a blinking yellow light next to all four of them.

I've tried stopping the carousel at the right spot and then unplugging the printer for a while in the hopes that it would wake up and find that all was well with the world -- this didn't help either.

Is there a home sensor somewhere I should look for and make sure it's clean?

What's the future look like for this particular printer since it dribbles cyan toner all over the inside?

Wow -- what a crappy printer!

For lack of nothing more intelligent to try, and because all other conventional means had failed, I did the following...

- Opened the top cover that gives access to the toner cartridges.
- Jammed a wadded lump of paper into the safety interlock on the left side near the cover's hinge so I could secretely spy on the deep, dark secrets of its inner workings. (Or in this case, non-workings.)
- Pressed the button to select a different toner cartridge and watched the carousel turn -- repeated the button push dozens of times staring blindly at the whirring machinations inside.
- Saw nothing unusual -- everything moves as it should except that it stops at the indentically wrong spot for each cartridge. At this point, what had been an internal self-dialogue consisting of an inventory of bewildering symptoms I was observing may have become verbal, loud and mixed with profanity -- I am not completely sure.
- Pressed the button yet again to select yet a different toner cartridge. Then on impulse, (borne from hours of sheer frustration) I risked bodily injury by reaching in and forcing the carousel to stop while it was in motion. (It didn't sound healthy, but didn't sound like I was breaking anything either. In any case, the sound was not nearly gratifying enough to satisfy my growing frustration.)
- At this point I stopped to refelct on my irrational act and justified it by smartly observing that the carousel brake would keep me from making any changes while the carousel was stopped -- only while the carousel was in motion was this sort of mechanical discipline possible!
- Noticed that subsequent moves of the carousel caused it to consistently stop in a new (still wrong) position each time. I was relieved to see that two things has apparently occurred. 1) I hadn't damaged the machine and wasn't bleeding anywhere. 2) The machine was now behaving differently by stopping the carousel at a new wrong spot each time.
- With new-found inspiration and a sense of purpose, I continued to risk bodily injury by repeating the stunt above where I would reach in a cause the carousel rotation to stall by grabbing it while it was in motion. Each time I was rewarded with the same unhealthy sound that somehow provided more gratifying as the these events unfolded.
- Repeated the process and observed the results. Each time getting a better feeling on when and where to stop the rotation to get the alignment I was seeking.
- Despite the long odds against it, I was able to keep all of my fingers and also get the carousel re-aligned. The printer is now happy and has printed hundreds of pages without further issues!
by mkrieger on Aug 17, 2006 at 10:38am Add comment

I am responding to this post EIGHT years later, but wanted to say this post made me laugh as I could relate completely to this horror, and did every step you did until I finally fixed it. It was a long, hard process in which I was also stubborn yet determined to fix the alignment even if it took pliers and risking bodily hand injuries!

Thanks for posting this, it gave me the confidence I needed to keep trying until I was able to fix it!! - lindseyS
Good job :) haven't come accross that problem yet but i can imagine i will one day
by Copafield on Aug 20, 2006 at 4:31pm Add comment
Arggh!! I just ran into this problem today, and it is good to see that I didn't have to break out the sledgehammer.

I will try that tomorrow. I had a POS radian cartridge (yellow) explode in the printer. messy as hell. Any other clues to get the stupid toner out of the cracks and stuff besides a lot of air at high pressures?

by ndeans on Sep 11, 2006 at 8:54pm Add comment
That is the best way to clean them. 120lbs. of pressure through a blow nozzle. Take it outside when you do so or everything around you will be yellow colored.
by moe on Sep 12, 2006 at 4:00pm Add comment
Help I have a blinking yellow light,no idea what it means or what I have to do to gt the printer to work...
by unknown on Sep 15, 2006 at 11:54pm Add comment
hi moe, would you have to clean the scanner out after blowing with air line, or is the scanner shutter very tight,
by shotgun on Sep 16, 2006 at 12:16am Add comment
If you get a copy of the maintenance manual you'll find there's a procedure for aligning the printer carousel. This involves unfortunately taking the entire machine apart, then once you have the carousel out, rotating a couple of gears till a couple of notches on the gears line up. The chances are that when you were taking everything apart to clean it you managed to mess up the alignment. Grabbing it while it was turning certainly changed the alignment. I did the same thing. I found it possible to download a copy of the maintenance manual here for $9.00.

I'd upload it here, but I don't know if I'd get in trouble for copyright violation.

by unknown on Mar 24, 2007 at 10:30pm Add comment
hi, all had another one today out of alignement, cst was complaning of toner light on even thou they had just changed it,
problem was carosel, so this time i just pulled carosel round on the right hand side and it clicked back in line with other side,
tested ok cst was happy and so was i....
by shotgun on Mar 29, 2007 at 9:55am Add comment
I have a similar problem. I changed cartridges and when I put the new cartridges in, it has thrown the alignment out. It is now only printing half a page (the right side). So it appears to be off horizontal alignment. Does anyone have any suggestions.
by unknown on Nov 26, 2007 at 6:10pm Add comment
Please refer to the link below on the hp website. Look for the post by David Zuts and hurry since the service manaul will only be up for a couple more days. Print out the instructions attached to the post. Not an easy job.
by dmzcompute on Nov 26, 2007 at 6:29pm Add comment
help me please,
i have the same problem, only printing the right side of the paper.
how do i allign the carousel?
i dont have any service manual...
by unknown on Apr 13, 2008 at 10:12am Add comment
Go to the link below and download both the 2550 and 2840 service manauls. You will need the 2550 manaul to get to the carousel and you will need the 2840 to show you how to index the carousel. Both have the same engine but the 2550 manual does not have the procedure.
by dmzcompute on Apr 13, 2008 at 10:18am Add comment
hi all, ive seen a lot of these now, and the fault seems to be (im sorry to say) was a reman issue causing the problems,
let me explain,
the carosel seems to be jumping teeth due to the mag rollers on some of the reman toners being so tight, when i tried to turn them they were very tight, so when the carosel turns and ingages the mag roller gear on the body of the printer to turn mag roller round something has to give, and its the carosel,
check all your toners by turning the mag rollers (in the right direction)in turn and you will find a tight one, then replace it, but the carosel is now out of alignemant, refer to manuel to realigne, some times you can slightly bend right hand carosel gear so teeth are not mesheing to put back on alignment,spin caroesel becouse ive had a number of theth missing on some and have had to replace the carosels on a few...
ps; to disingage the carosel push a red straw like the one that comes with WD40 down the white block near the door pivet on the right hand side, good luck alan - shotgun
I had the same problem, thanks to the comments in this thread (thank you mkrieger) I was able to fix the alignment problem but now I have another problem (how surprising with such a great printer!) the pages I try to print come out white ! I have all the supplies (consumables) in good condition, the page is pure white.
Any clue anyone?
by eco-voyageur on Aug 28, 2008 at 4:03pm Add comment

I had the same problem where my printer would act like it was printing, but it only kicked out blank pages. The internal carousel was out of index. I downloaded the Color LaserJet 2820, 2830, 2840 Parts, Service Manual.pdf manual from the above link, and on page 203 it shows a diagram of the internal gears.

I did have to tear the entire thing apart in order to even see the gears. The two notches on the smaller gear need to line up with the one notch on the larger gear - which they weren't. So, after some frustration and hurt fingers, I managed to pry the bigger gear away from the smaller gear enough to turn the smaller gear (repeat on left and right sides) and got it to realign.

I put everything back together and POOF! it started working again!

Thanks everyone!
by unknown on Dec 30, 2008 at 11:25am Add comment
So i had the carousel alignment problem(on a 2840). i managed to take the unit apart and re-align the carousel but now im having a problem when the unit turns on. When i turn the unit on the carousel tryes to spin and but it doesnt move. it just shakes and makes a sound like the motor is restricted. when i pull out the carousel motor and turn it on, it doesnt make the noise and hte motor works fine. i think a gear somewhere must be out of alignment but cant figure out where it is. Any ideas? thanks! Chris
by cmos on Jan 12, 2010 at 1:30pm Add comment
I am the IT guy for a company that has a a LaserJet 2840. It kept going out of alignment. It was still under an extended warranty. I fixed it myself once and two other times a warranty tech fixed it. Then one day it locked up. The office secretary called me. I checked and it was aligned. Scratched my head and asked exactly what happened. Seems she had just installed a new toner cartridge. That had me wondering. I pulled the cartridge and put the old one back in and it worked! They were using remanufactured toner cartridges purchased from for a long time. The new cartridge was slightly different! And it was locking up the whole carosel. So after confering with inkgrabber we got EXACTLY the right cartridges from then on and it never locked up again. Now for the bad news. 2 1/2 months ago it started jumping out of allignment once a week. The warranty was almost up so we called them. Three sevice techs later the diagnosis: Carosel gears worn out. Need replaced. the service guy said it is VERY common on this printer. Two weeks ago: no gears to be found by warranty company (OfficeMax). So they were just going to do a 'buyout'. Yesterday: the secretary called me and said she just got Visa card from the OfficeMax warranty company to be used only at OfficeMax for the entire original purchase price. What sucks is they have 4 new toner cartridges in stock for it they can not use now. I think I will try to locate a good carosel for it (if I can!)and fix it myself. - Anonymous
Today only the right vertical half the pages were printing. I took apart the machine to re-index the carousel. It was a 2-man job unless you're really technically handy. One of us read the instructions from the manual to the other and memorized the order the hardware was being removed. We put it back, but it did not solve the problem. A new problem came up, the printer did not recognize the memory slots so now it thinks it's a 2830 instead.

The post by shot gun about the cartridge's mag rollers being might be valid--I took all the cartridges out and tried to roll them and they all rolled except the black one which was impossible to roll, even by a strong man. I'm going to take the cartridge back to my refill guy and see if can loosen up the mag rollers.
by unknown on Feb 5, 2011 at 8:11pm Add comment
Every one I've ever done was the result of seized remanufactured cartridges. I don't ever take the beasts apart. All you need to do is insert a paper clip into the solenoid release hole and then you can spin the carousel and remove the toners. Then you line up the index marks on the left side and eyeball the ones on the right. They're the ones that jump out of time because that's the cartridge drive side. Then while holding the gear on the left, stick your finger under the gear on the right and pull inwards, then rotate in the direction it needs to go to align properly and let go. You might have to do it a couple or three times, but it saves over an hour of disassembly/reassembly and grief like you got with it losing its slots and memory.
If you put the remanufactured cartridges back in, then it's entirely possible that it jumped out of index again.
by moe on Feb 5, 2011 at 11:12pm Add comment
You sir (moe), are a bloody legend.

Thanks for this info - You saved me buying a new printer. Send me your paypal address and I will send you my thanks the old fashioned way. - slimf
I'm afraid I'm having trouble with this bit:
Then while holding the gear on the left, stick your finger under the gear on the right and pull inwards...

Is the "gear on the left" the gear on the left of where the cartridges are or the left gear on the right side of the cartridges (as viewed from the front of the machine)?
What do you mean by "pull inwards"? Is this pull the gear along the shaft towards the centre of the machine (to the left in that case)?

Andrew - aradke
HP2840 - prints vertical 1/2 page --I took my refurbished toner back to have the mag rollers loosened but my printer still only prints half a page. Can it really be the misaligned indexing? How come it didn't work the first time I took the thing apart? I may have to try taking it apart again.
by unknown on Feb 8, 2011 at 3:35pm Add comment
Read my post directly above. There is no reason to take it apart. Just stick the paper clip in and take the toners out. Rotate it until the yellow is facing you and look for the index marks. Align the one on the left and then use my technique to align the r/h one. I would never take one of those apart unless I absolutely had to.
by moe on Feb 8, 2011 at 4:59pm Add comment
Thanks Moe. I had a customer with a 2840 that was only printing on the right side of every page. When I checked the alignment the right side was off by one notch. I re-aligned it following your directions and it now prints perfectly.
by scout12 on Mar 22, 2011 at 10:09am Add comment
thank you to moe. hate bumping an old thread, but some of these things are still in existance. lol. and his advice is golden...i would not take one of these apart, as you never know what the customer will throw in there for a toner. i had a callback on 1 i "repaired", due to another tight reman'd toner they used.

question, though...where are the index marks on the right side?

thanks in advance.
by chris on Aug 8, 2011 at 12:39pm Add comment
I am having the same problem, all my color lights are on and blinking. i couldn't print a single document. before i do the repair myself i am asking you to look upon the service manual (uploaded by someone else) and tell how should do it, and please specify the page number from it.
by unknown on Sep 21, 2011 at 12:15pm Add comment
Big mistake to do it the HP way. That'll take you a couple of hours, a lot of disassembly and you're more likely to make it worse. My method, which is detailed above takes minutes and involves no disassembly. It is not shown in any service manual. Your choice. - moe
I'm having trouble figuring out where this solenoid release hole is supposed to be... and can't find anywhere to stick anything to get it to let me turn the carousel... I'm trying to fix a 2550, I've got 2 of them with misaligned carousels now :(
by unknown on Oct 25, 2011 at 11:41am Add comment
Nevermind, I looked at it from a different angle and finally found it, I was looking on the wrong side. I have one working printer now, will have to try to fix the other one later, thanks so much Moe!!
by unknown on Oct 25, 2011 at 12:34pm Add comment
It's funny how Moe and TMBMT will not give instructions on how to find that elusive paperclip hole :)

I searched and I don't have a clue what they are talking about.

Usually it's quite obvious where to insert my little paper clip, but not this time ;0
by unknown on Oct 27, 2011 at 6:46pm Add comment
lol Sorry TonerHater, look on the left side up near the top of the opening, there's a hole with a little metal lever behind it that gets hit when the lid comes down
by unknown on Oct 27, 2011 at 6:52pm Add comment
Hey thanks for the quick response - you know, I push those little metal levers, but the toner carousel remains locked. WTH!
by unknown on Oct 27, 2011 at 8:11pm Add comment
The release is on the right side. Look above the colored triangle on the carousel. You'll see the opening and inside a piece of white plastic. That's where you stick the paper clip. You'll know when it's released because the carousel will turn.
by moe on Oct 27, 2011 at 10:01pm Add comment
oh hm, I didn't and still can't find that one, the one I used on the left didn't release the carousel it just let me push the button to turn the carousel without having to open and close the door between every cartridge removal. I was able to adjust the right one with the carousel still locked, but then mine was only out by one tooth on each of my 2 printers (got the other one fixed by the way, woohoo!).
by unknown on Oct 27, 2011 at 10:41pm Add comment
TMBMT: That's exactly what I did last night to get the toners out.

Moe: I looked again and I can't find it. There is no colored triangle as far as I can tell. Can I email you a picture of mine?
by unknown on Oct 28, 2011 at 6:21am Add comment
Let me pinpoint it for you. Lift the top up. On each side, there is a curved piece of plastic that slides into the printer on a track. On each side of the printer, there is a track to slide your cartridge in. On each track, at the top there is a blue triangle pointed downward to indicate that you are supposed to insert the cartridge there. If you look at the one on the right and go up about an inch, you'll see an opening with a white piece of plastic that has a hole in it. Couldn't be easier.
by moe on Oct 28, 2011 at 10:16am Add comment
Thanks :) I see that opening, but it doesn't let me turn the carousel freely, when I stick something in.

I'm also not sure where those alignment marks are supposed to be.
by unknown on Oct 30, 2011 at 4:40pm Add comment
To unlock the carousel so it rotates freely see this 30 second youtube video on it. Do a youtbe search for " 2840 unlocking carousel" or a google search for printer repair videos & under the 1st one -- longlifeprinters --- choose the second video down which will go to the 30 second video.
by unknown on Nov 25, 2011 at 10:26pm Add comment
My previous Youtube listing for the video on Youtube got wiped out by accident. Sorry. Here is the new Youtube link: ---

Hope this helps you to unlock & rotate the carousel on a 2500 or 2840 to re-index the gears or to remove the toners by hand.
by HP-Printer-Dave on Jan 2, 2012 at 8:52am Add comment
Hey everybody,

for carousel problem, or toner misaligned be careful to the solenoid on the top of the printer which it used to stop the carousel on the right position.
The solenoid have a "foam" glued on it and with time this foam disappear. so it stay just the glue.
when the solenoid is in action, the solenoid lever glued during very less time on it and make a bad stop of the carousel.

hope this will help you.

by unknown on Jan 3, 2012 at 8:19pm Add comment
Yes, many HP magnetic clutches are now sticking in the open position too long because the feldt pad for quieting the clutches clicking noise, disintegrates leaving only the glue causing the metal arm to stick to the glue. since these old printers keep going, it is a good idea to either put celophane tape over where the "quieting pad" used to be or remove the clutch arm & scrape off the sticky glue. Now the clutch arm will click when opening but won't stick open. If taping over the sticky spot, use a 1.5 inch or so strip long enough to go over the brass looking circle that applies the magnitism & also over the back side of the "L" shaped metal. I haven't had tape fall off in over 5 years. A trick is to tape down a small bit of que-tip cotton where the pad used to be; I have sheets of replacement sticky back feldt I use on all these clutches; I just cut off a small strip for each one. I've seen it on the LaserJet 2500, 2550, 2840, 4000, 4050, 4100, 4200, 4, 4+, 5, 5si, 8000, 4500, 4550, etc. If you'r getting the 41.1 error on the 4000 or 4100 then it is probably sticky paper feed clutch arms.
by HP-Printer-Dave on Jan 9, 2012 at 11:41pm Add comment
You need to place something like a felt pad or electrical tape over the area you removed the glue. If you do not then the solenoid L arm will become magnetized causing worse issues. Only seems to be an issue with the 2500 series.
by dmzcompute on Jan 10, 2012 at 5:17am Add comment
hi all. So i have this "incorrect yellow" message on my hp 2820. Cartridges are ok, changed the whole rotary drive assembly,formatter,aligned the gears. Still the same error. I was wondering : has any of you changed the carousel on this machine due to this "incorrect yellow message"?
by unknown on Mar 21, 2013 at 2:24pm Add comment
It's the same sensor that reads all the toner cartridge chips as they rotate around. I would blame the chip first. I just was out on a service call complaining of loud squeaking. We always ask if they tried a new toner cartridge. They said yes, and of course it was another bad Office Depot cartridge in the printer. So, when you say the cartridges are OK, exactly what do you base that conclusion on? - moe
Great forum. I just got a 2550n for free. Now I know why. It came with a lot of toner and a new imaging drum. I'm old, disabled and retired so this gives me something to do besides vigorously excersing my buns on the couch. Same indexing problem and I am working on it right now. Tried the straw trick but that won't free the carousel. Should the power be ON for that to happen?
by Killarney on Jun 13, 2014 at 4:54pm Add comment
You have to stick it in the right place and push it in far enough to unlock the carousel. Make sure it's misaligned first as it could be a sticking solenoid. You can look at the ends of the cartridge and see if one end is out of alignment with the slot it goes down in. If they're both aligned, then you would want to fix the solenoid. I developed a surgical procedure that only requires removal of the cover, formatter and motor. Saves about 1/2 hour or more of disassembly per Service Manual procedure. - moe
Mine HP 2550n: s also stucked with cartridg not at their places plz some one help me
by sahir on Mar 7, 2015 at 10:26pm Add comment
Mine HP 2550n: s also stucked with cartridg not at their places plz some one help me
by sahir on Mar 8, 2015 at 1:39am Add comment
Not so hard to DIY.
Here's what you want.

Do as what youtube did and clean all the sticky things off.
Last step is don't forget to tape one or two rounds of tapes around the L-shape's metal. - healthup