Print quality troubleshooting

If the customer is using non-HP media and after the Image Quality Test you still have the same image quality problems, change to genuine HP media and repeat the Image Quality Test. The best alignment calibration is obtained using HP Photo Paper.

Nozzle Health

The print contains three separate parts.

a

b

 

 

 

c

 

 

 

 

 

 

 

 

 

aThe Variable Frequency Nozzle health plot with odd/even nozzles separation. This is used to detect misdirected nozzles, weak nozzles, or nozzles not working correctly at all frequencies.

bInspector measuring tool test plot.

Test b should NOT be used by Service Engineers.

cNozzle 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:

1On 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.

2On 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.

1Recover the Printheads using the option through the Front Panel (Main menu/Image quality maintenance/clean printheads).

HP Designjet T Series — Service Manual

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