Xc830 copying dark ,down center of page - Xerox 8830 Copier

There are a series of mirrors on the carriage that moves back and forth under the original glass. When dust builds up on these mirrors it makes the copies darker. Since the dust is blown by the optics cooling fan it does not collect evenly which causes areas of the copy to be darker than the others. On this machine you just have to remove the original guide plate which is the plate with 4 screws in it and has the document size numbers on it. Once that is removed the glass can be lifted out. With the power turned off just gently pull out the scanner bar. The part that initially comes out has 1 mirror as well as a silver reflecting strip on it. Clean both. Now the assembly that follows the first assembly out has 2 mirrors on it. 1 facing downward and 1 facing upward. Clean these 2 mirrors. Re-nstall the glass and plate. Turn the machine on and let the scanner unit home itself. Once warmed up make a copy to test. Cleaning these surfaces will usually correct the problem. There are 2 more mirrors under the black box under the glass but those do not get as dirty and they are harder to get to.
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