Colour misaligned on MP C400

[sandmanmac]

Just picked up an MP C400 that I'm going to resell, and it has a strange colour registration issue that in my short time with it, seems to only occur on the internal test pattern. In limited testing, prints from my laptop, and copies look good
The C,M,Y are all evenly shifted down the page by about 1mm (See attached).
I've done the usual line position SP's, including ACC recall, which has solved several line positioning issues for me in the past. ID sensors are clean, tried a different transfer belt, did an engine clear, and Firmware updated.
Any suggestions?

Thanks!

Test Pattern.pdf

[mikadonovan]

Hey, Sandy. I just ran a print test pattern on 2 c3300"s and a c5501 and compared them to your pattern. These are machines that are working fine with no issues. Other than maybe a slight skew on your pattern from the scan, they all look identical. If your prints and copies are good, I would say no worries.

[sandmanmac]

Thanks for that, Mika...
Since the only issue seemed to be with the test pattern, I decided to risk it, and delivered the machine today.
It seems that it enjoyed bouncing around in my van for an hour or so, because the test pattern and everything else was perfect once I got it on site.
It's a head scratcher!!

[slimslob]

Hey, Sandy. I just ran a print test pattern on 2 c3300"s and a c5501 and compared them to your pattern. These are machines that are working fine with no issues. Other than maybe a slight skew on your pattern from the scan, they all look identical. If your prints and copies are good, I would say no worries.

If you look at the R B & G color grey scales, they should be centered in the black box and are not. same in all other places where the colors are supposed to line up with the black.

[sandmanmac]

I'm re-opening this thread, because the situation with the machine has gotten worse, and I've noticed some other peculiar things:
The colour shift from my original post has gone from about 1mm to 2+mm and is now affecting the print quality.
The line position adjustment (including ACC recall SP's) does not correct the problem, yet the adjustment always completes successfully with no errors.
I printed out the non-default data, and it was just over a single page of data, when it should be 3+ pages.
I've attached the first page of the printout from both a good machine and the one in question, for comparison.
I played around with the colour registration settings (specifically SP101-01 06 thru 08) on a machine at my shop, and was able to duplicate the issue exactly, so I returned to the client and manually set the registration in order to correct it for the time being.
I did swap in another ITB unit, and had the exact same results.
I also attached the self diagnosis page showing the Firmware Levels. They may not be the most current ones, but they are the most current I have available to me. The client's machine, as well as my other unit, have the exact same levels installed.
I'm probably going to go back and try re-writing the firmware, but I would definitely appreciate any feedback that anyone has to offer.
Non-Defaults - Bad.pdf
Non-Defaults -OK.pdf
Colour test pattern.pdf
Self Diag.pdf

[Polarbear]

I'm re-opening this thread, because the situation with the machine has gotten worse, and I've noticed some other peculiar things:
The colour shift from my original post has gone from about 1mm to 2+mm and is now affecting the print quality.
The line position adjustment (including ACC recall SP's) does not correct the problem, yet the adjustment always completes successfully with no errors.
I printed out the non-default data, and it was just over a single page of data, when it should be 3+ pages.
I've attached the first page of the printout from both a good machine and the one in question, for comparison.
I played around with the colour registration settings (specifically SP101-01 06 thru 08) on a machine at my shop, and was able to duplicate the issue exactly, so I returned to the client and manually set the registration in order to correct it for the time being.
I did swap in another ITB unit, and had the exact same results.
I also attached the self diagnosis page showing the Firmware Levels. They may not be the most current ones, but they are the most current I have available to me. The client's machine, as well as my other unit, have the exact same levels installed.
I'm probably going to go back and try re-writing the firmware, but I would definitely appreciate any feedback that anyone has to offer.
Non-Defaults - Bad.pdf
Non-Defaults -OK.pdf
Colour test pattern.pdf
Self Diag.pdf

Colour registration issues, when settings don't help, point to the laser unit in most cases, as the mirrors have to move (except for black) to dial the images into place.

Have you tried another laser unit?

[zed255]

I had an issue like yours recently and ended up replacing the ID sensor assembly. Dialed itself in right away.

[sandmanmac]

Colour registration issues, when settings don't help, point to the laser unit in most cases, as the mirrors have to move (except for black) to dial the images into place.

Have you tried another laser unit?

I had an issue like yours recently and ended up replacing the ID sensor assembly. Dialed itself in right away.

Thanks for the advice. I'll be dropping back in next week for another go, and I'll report back with the results.
I guess I was expecting an SC message if the laser or ID sensor was the culprit, and the missing Data on the printout got me thinking about maybe an NVram issue or something

[sandmanmac]

I finally got back to the client. They do very little colour printing, but as far as I know it had been running fine with my manual settings for a few weeks (although I foolishly neglected to print a sample page before replacing the ID sensor) .
The ID sensor did nothing to resolve the problem, and the C/M/Y were all still shifted after making the adjustments. So I guess the next step will be the laser unit as Polarbear suggested?
As a reminder, here's a copy of the most recent colour pattern:
MOWC - Sample.pdf

[slimslob]

It looks like the colors are too far off for the color registration to be able to correct it. Before going the cost of a new laser unit you might want to try doing a manual adjustment. Since all three colors appear to align to each other and only the black is off, try changing SP 2101-001 and see if the black moves in reference ti the colors and in what direction. If it does, but not enough or in the wrong direction, try a different value.