DC 240 CK ROS replacement

**printprocc** · 12-28-2015

Good morning folks,
I recently had to chase down the faded cyan stripe on my print outs and as expected found a bit of toner spray on the CK ROS glass window. I figured it would be a good time to open the top as I have done many time before to make sure the mirrors were clean and found toner in there as well. After thorough cleaning with a Qtip I put the ROS assembly back in and anticipated nice clean prints only to end up with Cyan not printing at all. Figuring I somehow disrupted one of the mirrors internally (odd as I didn't apply any pressure and made sure nothing moved) I opened the machine back up and double checked and all seemed fine. OK long story short I never could get the machine to print Cyan again so I took a used CK ROS assembly from a parts machine I have and put it in. Now the machine prints all colors again however the prints are now off in color. Spot colors are not all accurate and so on. I have attempted re calibrating but only end up getting the "measured density is lower than expected values" error message. I have also performed numerous Auto Gradations to no avail. What am I missing?? I assume there is some sort of procedure that I needed to follow when putting in a different or new ROS assembly but I don't know what that might be.

Xerox Docucolor 240 with Creo cx250-5350 color server.

**Exok** · 12-28-2015

The only adjustment that the edoc tells you to run after installing the ROS is Registration Control Setup Cycle in Diagnostic Mode using a PWS.
It says to select dC956 from the DC Quick menu then dC675 from the DC Quick menu.

One thing that can be a real pain is getting the ribbon cable correctly seated. That could have been the problem you were having with your original ROS. I've heard a number of people over the years talk about having to reseat that ribbon cable over and over to get it positioned correctly.

**printprocc** · 12-29-2015

Thank you Exok,
I too did not find anything in the EDOC regarding any other adjustments but the ones you mentioned. I went in and out so many times trying to get the original ROS to work, I probably made things worse but was happy to discover on the first try the replacement unit worked. I will run the 2 steps you mentioned and see where it takes me but I'm chasing other issues with it as well. Can't seem to get rid of an error message when i try to calibrate the machine. "Measured density is lower than expected values". Did Auto Gradation and even tried adjusting tone control to no avail. Oh well, at least it runs. Thanks again.

**XeroxTechBrazil** · 12-31-2015

Check your IOT software level as well,, later software keeps the machine a lot cleaner and reduces dirt on ROS mirrors.

A powerpoint presentation in the attached file discuses 240/250 ROS contamination.

**printprocc** · 12-31-2015

Thank you. That was very informative. I will check that software level when I get back in front of that machine.

Happy New Year.

**printprocc** · 01-06-2016

Good morning again folks,
Thought I would give an update regarding my continued struggle trying to calibrate this machine and unfortunately I am still a bit stuck. Ever since changing out the CK Ros assembly, those 2 colors have not been printing up to proper density. Dozens of attempts to calibrate off the glass have failed. As mentioned above, I have also performed auto gradation which did seem to make copy quality improve, it has not changed my calibration issue. I had assumed it was possible that the lighter copy density was at fault for low scan density when attempting to calibrate but that's apparently not it. I have also gone in and tried to do adj 5.11 IIT Calibration but can only go as far as doing the white Reference adjustment. I can't do the CCD Calibration because I don't have a "Color Test Pattern". One thing to mention is that I do not believe my calibration issues are a result of changing the ROS assembly as I had been having on and off again issues with that for some time. In the past month I have replaced all 4 drums, 2 developer housings (one of which was Cyan) with new developer in each, a new IBT belt and all four btr rollers. Am I missing something?? Obviously I must be.

**vision-perfect** · 01-09-2016

Originally Posted by printprocc

Good morning again folks,
Thought I would give an update regarding my continued struggle trying to calibrate this machine and unfortunately I am still a bit stuck. Ever since changing out the CK Ros assembly, those 2 colors have not been printing up to proper density. Dozens of attempts to calibrate off the glass have failed. As mentioned above, I have also performed auto gradation which did seem to make copy quality improve, it has not changed my calibration issue. I had assumed it was possible that the lighter copy density was at fault for low scan density when attempting to calibrate but that's apparently not it. I have also gone in and tried to do adj 5.11 IIT Calibration but can only go as far as doing the white Reference adjustment. I can't do the CCD Calibration because I don't have a "Color Test Pattern". One thing to mention is that I do not believe my calibration issues are a result of changing the ROS assembly as I had been having on and off again issues with that for some time. In the past month I have replaced all 4 drums, 2 developer housings (one of which was Cyan) with new developer in each, a new IBT belt and all four btr rollers. Am I missing something?? Obviously I must be.

Hi i have a similar problem.

Look:

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