Canon imagePROGRAF GP-4000 - Manual (Page 745)

Problems with the Printing Quality
Printing is faint
Paper rubs against the Print Head
The edges of the paper are dirty
The surface of the paper is dirty
The back side of the paper is dirty
Immediately after borderless printing, the trailing edge margin is soiled during
regular printing
Printed colors are inaccurate
Banding in different colors occurs
Colors in printed images are uneven
Image edges are blurred or white banding occurs
The length of the printed image in the paper ejection direction is not accurate
Images are printed crooked
Documents are printed in monochrome
Line thickness is not uniform
Lines or colors are misaligned
Borders appear in borderless printing
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