HP Designjet 4000 Printer series - Manual (Page 180)

How do I interpret Image Diagnostics part 2?
The purpose of part 2 is to test whether the printheads and the paper advance
mechanism are working correctly. This part of the print should not be used to check
for color consistency or accuracy.
Banding
Banding has occurred when you see repetitive horizontal bands within the printed
image. They can appear as light bands:
or dark bands:
Chapter 11
178
How
do
I use
the
Image
Diagnostics
Print?