HP DesignJet T770 User Manual

17 Troubleshooting ink cartridge and
printhead issues
●Cannot insert an ink cartridge
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Ink cartridge status messages
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Cannot insert a printhead
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The front-panel display recommends reseating or replacing a printhead
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Clean the printheads
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Clean the printhead drop detector
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Align the printheads
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Printhead status messages
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Ink system issues
 

Cannot insert an ink cartridge
1.Check that you have the correct type of cartridge (model number).
2.Check that the colored label on the cartridge is the same color as the label on the slot.
3.Check that the cartridge is correctly oriented, with the letter or letters marking the cartridge label
right-side up and readable.
CAUTION:Never clean inside the ink cartridge slots.
Ink cartridge status messages
These are the possible ink cartridge status messages:
●OK: the cartridge is working normally, with no...

4.Clean the electrical connections on the backside of the printhead with a lint free cloth. You can
carefully use a mild rubbing alcohol if moisture is needed to remove residue. Do not use water.
CAUTION:This is a delicate process and may damage the printhead. Do not touch the
nozzles on the bottom side of the printhead, especially not with any alcohol.
5.Reinsert the printhead, see Insert a printhead on page 120.
6.Check the front-panel display message. If the problem remains, try a new printhead.
Clean...

1.Turn off the printer at the front panel.
2.To avoid an electric shock, switch the printer off and unplug it.
3.Open the window.
166 Chapter 17   Troubleshooting ink cartridge and printhead issues ENWW
Ink system issues
 

4.Find the printhead drop detector beside the stored printhead carriage.
5.Remove any debris blocking the printhead drop detector.
6.With a dry lint free cloth, wipe the surface of the drop detector to remove any non-visible debris.
7.Close the window.
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Ink system issues
 

8.Plug in and switch on the printer.
9.Power the printer on at the front panel.
Align the printheads
Precise alignment between printheads is essential for accurate colors, smooth color transitions and
sharp edges in graphical elements. Your printer has an automatic printhead alignment process which
runs whenever a printhead has been accessed or replaced.
In cases where the paper has jammed or you are experiencing problems with color accuracy, see
Color management on page 65; you may need to align the...

4.Ensure the window is closed, as a strong light source near the printer during printhead
realignment can affect alignment.
5.The process takes about six minutes. Wait until the front-panel display shows the process
complete before using the printer.
NOTE:The printer prints a calibration image. Do not worry about the image. The front-panel
display shows any errors in the process.
Image Quality Maintenance menu procedure
1.Load the paper you wish to use, see Paper handling on page 31. You can use a roll...

Scanning errors during alignment
If the alignment process fails, a Scanning problems message appears on the front panel. This means
that the alignment has not completed successfully. Therefore the printer is not aligned and the
alignment should be repeated before printing with good image quality. The problem may be due to:
●The paper used was not valid, repeat the alignment with valid paper
●Printhead health problems, clean printheads, see 
Clean the printheads on page 165
●The alignment was done with...

18 Troubleshooting general printer issues
●The printer will not start
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The printer does not print
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The printer seems slow
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Communication failures between computer and printer
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Cannot access the HP Utility
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Cannot access the Embedded Web Server
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Automatic file system check
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An AutoCAD 2000 memory allocation error
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No output when printing from Microsoft Visio 2003
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Unavailable driver features when printing from QuarkXpress
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Printer alerts
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General printer issues
 

The printer will not start
If the printer will not start (the front panel is blank or the diagnostic LEDs are all off), you are
recommended to replace the firmware, in the following way.
1.Go to the Knowledge Center (see 
Knowledge Center on page 180) and download the firmware.
2.Save the firmware on a USB flash drive. Ideally, the USB flash drive should be empty and
formatted with the FAT filesystem.
3.Ensure that the printer is turned off. Connect the USB flash drive to the printers USB port, then
turn...