Question about Canon NP 6551 Black and White Copier

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Grey background on copies from a Canon 6551

Service tech told me I need to replace Developer Unit. Total cost is close to $800. The age of the copier makes this too costly a replacement. Any options or ideas are needed to keep this copier functioning. Please help!

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  • mgivan Nov 25, 2008

    Dumped all the toner from the developer unit and hopper unit, vacuumed out any excess, replaced with a fresh bottle of toner and ran toner function. PROBLEM SOLVED!

    I have replaced toner before when I got a bad batch, but when the tech told me it was the unit itself, I took his word for it and did not try the first thing that came to mind, which was the solution recommended by Cogz. Thank you for the help. I have to remember that techs are usually right, but trying that one last thing can save you a bundle and get you up and running again.

    Again, thank you very much.



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Yes, there maybe one thing that can also cause this problem.. You may have a bad or contaminated toner. You can have the all of the toner vacumed out of your hopper unit and removed from the developer unit and have underneath the dev. mag roller vacumed out and restart or install a New OEM toner back into the hopper and have them run a install toner funcation. That should take care of your problem. Even if you just change the developer unit you will still be using the same bad toner it all needs to be removed. I only really say a copier get contaminated more then once, was where the copier was in a very,very Cold room. The toner get water dew in them and the toner clumps. And you get grey and a modeled back ground and bad C.Q..... Good Luck

Posted on Nov 23, 2008


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