Canon iR C6800 Series Service Manual page 923

Chapter 13
13.3.2.6.3 Stray Toner
0005-5806
<Cause>
When solid color double sided prints are made in a low humidity environment, the inadequate secondary transfer
current for the 2nd side can cause stray toner.
<Field Remedy>
Limit the amount of color toners by executing the following service mode items:
Set 3 to the following in service mode: COPIER>ADJUST>COLOR>ADJ Y.
Set 3 to the following in service mode: COPIER>ADJUST>COLOR>ADJ M.
Set 3 to the following in service mode: COPIER>ADJUST>COLOR>ADJ C.
Set 3 to the following in service mode: COPIER>ADJUST>COLOR>ADJ K.
<Caution>
If the image is too faint, increase the setting by using the foregoing service mode items. After performing this remedy,
be sure to execute full correction in user mode (under auto gradation correction) to ensure optimum density.
<Remarks>
This symptom can occur when printing on the 2nd side of dry paper while making a double side print of solid color
images in a low humidity environment.
Advise the user to avoid the use of paper that has been left alone for a long time whenever possible, recommending
the use of paper fresh out of package.
F-13-38
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