HP DesignJet Z2100

Designjet Z Series — Service Manual 1-37
Reading the Advanced Diagnostic Print Results
to check if you see any missing parts of the plot, banding or white streak
in them.
b Inspector measuring tool test plot.
c Nozzle Print Test which is also part of the Image Quality Service Plot.
This test is designed to check that the Printhead nozzles print correctly.
The test prints out every single nozzle of each Printhead. No error hiding
or Printhead Alignment algorithm is applied. For each Printhead, you can
see both the adjacent and the consecutive nozzles.
This is what you would see in the Nozzle Print Test part if there are
nozzles not printing correctly:
1 On the right of each Printhead Nozzle test, there is a series of numbered
stepped diagonal lines. If one or more of the nozzles are malfunctioning or
mis-positioned, you will see that the stepped lines are broken or misdirected
in one or more places.
2 On the left of each Printhead Nozzle test, there is a series of horizontal
straight lines. If one or more nozzles are misdirected there will be unequal
spaces between the corresponding lines.
Corrective Action for Nozzle Defects
If the printer has nozzle defects, it does not mean that you will not get
perfect print quality results. The printer has automatic procedures to hide
many nozzle defects.
1 Recover the Printheads using the option through the Front Panel (Main
menu/Image quality maintenance/clean printheads).
2 Reprint the Nozzle Print test to check that the defective nozzles have been
corrected.
3 If the problem continues, replace the defective Printhead.
Force Drop Detection
If the Nozzle Print Test plot has persistent white point banding in only
one color that cannot be fixed with a printhead recovery, you can use this
option to resolve the problem by resetting the nozzle health data base so
that all nozzles are assumed to be correct.
Once the nozzle health data base has been reset drop detection is forced.
The normal cause of this white point banding in a single color is the
incorrect detection of failed nozzles by the drop detector.
Test b should NOT be used by Service Engineers.