MPC3000 SC285 prob

[Blazer1087]

Hi everyone. We got an mpc3000 in the shop that fails the color registration precedure. I exchanged the transfer belt unit, tried the 285 recovery precedure, cleaned the ID sensors, nothing changed. The black copy was pretty weak so I tried another PCU. Still the same. Is there a way to print out the Line adj. pattern to look at and see if some lines are not printing? Is there something else I should try? Thanks for any help.

[JustManuals]

This Parts & Service manual can now be purchased for $12.77 and downloaded immediately after payment from
Just Manuals | The Internet's largest selection of manuals | Instant Downloads


Paul@justmanuals.com

[Blazer1087]

?? I have the manual, thank you.

[jonezy999]

Check to see what pattern is missing on the belt when the machine fails.

Ooops, just read ur post again, If its out of register, can you run ACC and see which colour is out from the printout?

[Gary Bowen]

It sounds like you started to go in the right direction, but got side tracked. You mentioned that the Black was light; if any of the colours are light your line position adjustment will not pass. You need to do SP3015-003 (Forced Toner Supply K); check your CQ/Density after each time you execute this. If your CQ/Density is OK, do your Process Control Manual Execute (SP3011-001). Right now I would suspect your Process Control Self Check Result (SP3012) does not read "11111111"; successful completion of Process Control should get your Line Position Adjustment to work correctly. If you get any result for Process Control other than "11111111" troubleshoot that first; the order of the colours are Y C M K.

[Blazer1087]

I will check this tomorrow. If say the last two didgits of the process control result are not 11, does that indicate a problem with the black?
also all four of the colors appear out of register when I run a color copy

[teebee1234]

All of the colors are registered from the black "pole" position, so that will cause this issue.

From Detailed Descriptions...

Sub scan line position for YCM
The adjustment of the sub-scan line position for YCM is based on the line position for K
(color registration). The machine measures the gaps between the lines of each color in the
pattern on the transfer belt. If the gaps for a color are not correct, the machine moves the
image of the color up or down the sub scan axis. To do this, it changes the laser write timing for that color.

[Gary Bowen]

Section 4.1.2 of the Service Manual gives a list of the Process Control Self Check Reults. Each colour will show "11" if successful. Your colours will not align until the SC285 error is resolved and your description said the Black density is light - resolve that first. Remember, if you execute Forced Line Position Adjust SP2111 execute "c" first and execute "a" twice; the "c" adjustment is your coarse adjustment.

[Blazer1087]

Thank You.

[Blazer1087]

Still working on this one, lucky its not in the field. The process control result was good. Tried another PCU and the black copy is still bad. On letter going LEF the copy is ok on the side towards the back of the machine and faids to nothing on the side towards the front of the machine. Im guessing thats why to color registration fails. Making an all yellow, magenta, or cyan copy is dark but even from edge to edge. Allready tried transfer belt unit. Can something go wrong in the laser unit to cause the uneven black copy? Allready took it out and cleaned the slit glass's, opened it up and didn't see anything I wanted to mess with.

[teebee1234]

I've seen the mirror surface on the poly motor get "sandblasted" on the trail edge, causing the beam to scatter as it sweeps across. There are 2 mirrors stacked with the 4 beams hitting opposing sides. I've seen it happen to Magenta and Cyan in the past, probably due to some kind of contaminant getting inside the Laser Unit. Shine a light on the mirrors and look for any dullness.

[Blazer1087]

I will check this tomorrow. Wouldn't this affect more than just the black quality?

[teebee1234]

After rereading the post, I realized I was thinking of a specific problem I had on a 3245c. Many have posted that the shutter will give this issue (not fully opening square). Try removing the shutter and see if that affects it. There is a tech bulletin that addresses low density due to the shutter opening incorrectly, the sample shows black only having light density. It's related to firmware, update engine to V1.11.01.

Also found this in the Knowledge Base.....

[Symptom]
Transfer does not occur or prints are faded on one side (rear).
It is faded like a gradation in the main scan direction.
It occurs with both single color and full color. It sometimes occurs when using only special colors or when using all colors.
[Cause]
The operation of the dust protector shutter of the write unit is faulty.
There doesn't appear to be a problem with the shutter slide operation; however, the problem occurs because it does not open completely.
[Resolution]
Replace the write unit's dust protection shutter part with a new part (B2211852).

[Gary Bowen]

I agree with teebee; remove the shutter mechanism from the laser housing and try it again. I have had 1 MP C2500 where I had to replace the laser housing because the black was uneven top to bottom; C Y and M wre all OK - I ran Test Pattern 11 to get a close look at the toner laydown and was choked to think I needed to replace the laser, but this solved my uneven black laydown.

[Gift]