HP OfficeJet Pro K550 User Manual

							To align the printheads
Whenever you replace a printhead, the printer automatically aligns the printheads to ensure the best
print quality. However, if the appearance of your printed pages indicates that the printheads are
misaligned, you can start the alignment process manually.
●
Control panel: Press and hold 
 (Power button), press  (Resume button) 2 times, and
release 
 (Power button).
●Embedded Web server: Click the Settings tab, click Printer Services in the left pane, select
Align printheads from the drop-down list in the Print Quality section, and click Apply.
●Printer driver (Windows): Click the Services tab. For Windows 2000, Windows XP, and
Windows Server 2003, click the Service this Device button (this option is available only if the
Toolbox is installed), and then click the Printer Services tab. Click Align Printheads and follow
the onscreen instructions.
●Toolbox (Windows): Click the Printer Services tab, and then click Align Printheads and follow
the onscreen instructions.
●HP Printer Utility (Mac OS): Click Align from the Information and Support panel.
To calibrate the linefeed
●
Control panel: Press and hold  (Power button), press  (Resume button) 3 times, and
release 
 (Power button).
●Embedded Web server: Click the Settings tab, click Printer Services in the left pane, select
Calibrate Linefeed from the drop-down list in the Print Quality section, and click Apply.
●Printer driver (Windows): Click the Services tab. For Windows 2000, Windows XP, and
Windows Server 2003, click the Service this Device button (this option is available only if the
Toolbox is installed), and then click the Printer Services tab. Click Calibrate Linefeed and
follow the onscreen instructions.
●Toolbox (Windows): Click the Printer Services tab, and then click Calibrate Linefeed and
follow the onscreen instructions.
●HP Printer Utility (Mac OS): Click Calibrate Linefeed from the Information and Support panel.
To clean the printheads
NOTECleaning uses ink, so clean the printheads only when necessary.
The cleaning process takes up to 3.5 minutes. Some noise might be generated in the process.
●
Control panel: Press and hold  (Power button), press  (Resume button) 6 times, and
release 
 (Power button).
●Embedded Web server: Click the Settings tab, click Printer Services in the left pane, select
Clean printheads from the drop-down list in the Print Quality section, and click Apply.
●Printer driver (Windows): Click the Services tab. For Windows 2000, Windows XP, and
Windows Server 2003, click the Service this Device button (this option is available only if the
ENWWMaintaining the printheads 33
 
						

							Toolbox is installed), and then click the Printer Services tab. Click Clean Printheads and follow
the onscreen instructions.
●Toolbox (Windows): Click the Printer Services tab, and then click Clean Printheads and
follow the onscreen instructions.
●HP Printer Utility (Mac OS): Click Clean from the Information and Support panel.
To clean the printhead contacts manually
After printheads are installed, if one or both printhead lights on the control panel begin to blink and
the printer will not print, you might need to clean the electrical contacts on the printheads and in the
printer.
CAUTIONClean the electrical contacts only after you have attempted to clean the
printheads. See 
To clean the printheads. Electrical contacts contain sensitive electronic
components that can be damaged easily.
1.Open the top cover.
2.
If the carriage does not move to the left automatically, press and hold 
 (Resume button) for 3
seconds. Wait for the carriage to stop moving, then, unplug the power cord from the printer.
3.Lift the printhead latch.
4.Lift the handle of the printhead (which corresponds to the blinking printhead light) and use it to
pull the printhead out of its slot.
5.Obtain clean, dry, soft and lint-free cleaning material. Suitable materials include paper coffee
filters and eyeglass lens cleaning paper.
CAUTIONDo not use water.
34 Chapter 4   Maintaining and troubleshooting ENWW
 
						

							6.Wipe the electrical contacts on the printhead but do not touch the nozzles.
NOTEThe electrical contacts are small copper-color squares, grouped on one face of
the printhead.
The nozzles are on a different face of the printhead. Ink will be visible on the nozzles.
CAUTIONTouching the nozzles can cause permanent nozzle damage. Also, ink can
permanently mark clothing.
7.After cleaning, place the printhead on a sheet of paper or paper towel. Make sure the nozzles
are facing up and are not in contact with the paper.
8.Clean the electrical contacts in the printhead slot inside the printer with a clean, dry, soft and lint-
free cloth.
9.Plug in the power cord and turn on the printer. The control panel should indicate that the
printhead is missing.
10
.Insert the printhead into its color-coded slot (the label on the printhead must match the label on
the printhead latch). Press down firmly on the printhead to ensure proper contact.
11
.Pull the printhead latch all the way forward, and then press down to ensure that the latch is
properly engaged. You might have to apply some pressure to engage the latch.
12
.Where necessary, repeat the above steps for the remaining printhead.
13
.Close the top cover.
ENWWMaintaining the printheads 35
 
						

							14
.If one or both the printhead lights still blink, repeat the cleaning procedure described above for
the printhead which corresponds to the blinking printhead light.
15
.If one or both the printhead lights still blink, replace the printhead which corresponds to the
blinking printhead light.
16
.Wait while the printer initializes the printheads and prints the alignment pages. If the printer does
not print the pages, start the alignment process manually (see 
To align the printheads).
To replace the printheads
NOTETo find out which printheads work with your printer, see Supplies.
1.Open the top cover.
2.
If the carriage does not move to the left automatically, press and hold 
 (Resume button) for 3
seconds. Wait for the carriage to stop moving.
3.Lift the printhead latch.
4.Lift the handle of a printhead and use it to pull the printhead out of its slot.
5.Remove the new printhead from its package, and then remove its orange protective caps.
6.Insert the printhead into its color-coded slot (the label on the printhead must match the label on
the printhead latch). Press down firmly on the printhead to ensure proper contact.
7.Pull the printhead latch all the way forward, and then press down to ensure that the latch is
properly engaged. You might have to apply some pressure to engage the latch.
8.Close the top cover.
9.Wait while the printer initializes the printheads and prints the alignment pages. If the printer does
not print the pages, start the alignment process manually (see 
To align the printheads).
36 Chapter 4   Maintaining and troubleshooting ENWW
 
						

							Calibrating the color
Whenever you replace a printhead, the printer automatically calibrates the colors to ensure the best
print quality. If you are not satisfied with the appearance of the colors, you can start the color
calibration process manually.
●
Control panel: Press and hold 
 (Power button), press  (Cancel button) 2 times, and release
 (Power button).
●Embedded Web server: Click the Settings tab, click Printer Services in the left pane, select
the option to calibrate color from the drop-down list in the Print Quality section, and click Apply.
●Printer driver (Windows): Click the Services tab. For Windows 2000, Windows XP, and
Windows Server 2003, click the Service this Device button (this option is available only if the
Toolbox is installed), and then click the Printer Services tab. Click Calibrate Color and follow
the onscreen instructions.
●Toolbox (Windows): Click the Printer Services tab, and then click Calibrate Color and follow
the onscreen instructions.
●HP Printer Utility (Mac OS): Click Calibrate Color from the Information and Support panel.
ENWWCalibrating the color 37
 
						

							Troubleshooting tips and resources
Use the following tips and resources to resolve printing problems.
●For paper jam, see 
Clearing jams.
●For paper-feed problems, such as the paper skew and paper pick, see 
Resolving paper-feed
problems.
Some printer problems can be resolved by resetting the printer.
To reset the printers network settings (HP Officejet Pro K550dtn/K550dtwn)
1.
Press and hold 
 /  (Configuration Page button), press  (Resume button) 3 times, and
release 
 /  (Configuration Page button). The Power light blinks for a few seconds. Wait till the
Power light is on.
2.
Press 
 /  (Configuration Page button) to print the configuration page and verify that the
network settings have been reset. By default, the network name (SSID) is hpsetup and the
communication mode is ad hoc.
38 Chapter 4   Maintaining and troubleshooting ENWW
 
						

							General troubleshooting tips
Ensure the following:
●Power light is on and not blinking. When the printer is turned on for the first time, it takes
approximately 8 minutes to initialize the printer after the printheads are installed.
●Make sure the printer is in the ready state. If lights are on or blinking, see 
Printer lights reference.
●No error messages appear on the computer screen.
●Power cord and other cables are working, and are firmly connected to the printer. Make sure the
printer is connected firmly to a functioning alternating current (AC) power outlet, and is turned on.
See 
Electrical specifications for voltage requirements.
●Media is loaded correctly in the tray and is not jammed in the printer.
●Printheads and ink cartridges are properly installed in their correct color-coded slots. Press down
firmly on each one to ensure proper contact. Ensure you have removed the orange protective
caps from each printhead.
●Printhead latch and all covers are closed.
●Rear access panel (HP Officejet Pro K550) or duplex unit (HP Officejet Pro K550dtn/K550dtwn)
is locked into place.
●All packing tapes and materials are removed from the printer.
●Printer can print a configuration page. See 
Understanding the configuration page.
●The printer is set as the current or default printer. For Windows, set the printer as the default in
the Printers folder. For Mac OS, set the printer as the default in the Chooser or the Print Center.
See your computers documentation for more information.
●Pause Printing is not selected if you are using a computer running Windows.
●You are not running too many programs when you are performing a task. Close programs that
you are not using or restart the computer before attempting the task again.
ENWW General troubleshooting tips 39
 
						

							Resolving printing problems
Printer shuts down unexpectedly
Check the power and power connections
▲Make sure the printer is connected firmly to a functioning alternating current (AC) power outlet.
See 
Electrical specifications for voltage requirements.
Check the printer vents
▲The printer vents are located on the sides of the printer. If the vents are covered and the printer
overheats, the printer automatically turns off. Make sure the vents are not covered and the
printer is in a cool, dry location. See 
Environmental specifications for the required operating
environment for the printer.
All printer lights are on
A non-recoverable error has occurred
▲Disconnect all cables (such as power cord, network cable, and USB cable), wait about 20
seconds, and reconnect the cables. If the problem persists, visit HP website (
www.hp.com/
support/officejetprok550) for the latest troubleshooting information, or product fixes and updates.
Printer is not responding (nothing prints)
If the printer supports wireless communication, see also Problems setting up or using wireless
communication.
Check the printer setup
▲See 
General troubleshooting tips.
Check the printhead initialization
▲When printheads are installed or replaced, the printer automatically prints a few alignment pages
to align the printheads. This process takes about 8 minutes. Until this process is complete, only
the automatic alignment pages can be printed.
Check the printer software installation
▲If the printer is turned off when printing, an alert message should appear on your computer
screen; otherwise, the printer software might not be installed correctly. To resolve this, uninstall
the software completely, and then reinstall the printer software. See 
Uninstalling the printer
software.
40 Chapter 4   Maintaining and troubleshooting ENWW
 
						

							Check the cable connections
●Make sure both ends of the network cable are secure.
●If the printer is connected to a network, check the following:
●Check the Link light on the back of the printer. See 
Interpreting network connector lights.
●Make sure you are not using a phone cord to connect the printer.
●The network hub, switch, or router is turned on and working properly.
Check the printer setup for network environment
▲Ensure the correct printer driver and printer driver port are being used. For more information
about network connections, see 
Configuring the printer (Windows), Configuring the printer (Mac
OS), or the documentation provided by your network vendors.
Check any personal firewall software installed on the computer
▲The personal software firewall is a security program that protects a computer from intrusion.
However, the firewall might block communication between the computer and the printer. If there
is a problem communicating with the printer, try temporarily disabling the firewall. If the problem
persists, the firewall is not the source of the communication problem. Re-enable the firewall.
If disabling the firewall allows you to communicate with the printer, you might want to assign the
printer a static IP address and re-enable the firewall. See 
Configure network settings.
Printer does not accept printhead
Check the printhead latch
▲Make sure the printhead latch is properly closed.
Check the printhead
●Make sure the printhead is inserted into its correct color-coded slot. See 
To replace the printheads.
●Remove the printhead, and check to make sure the orange protective caps have been removed
from the printhead.
Clean the printhead
▲Complete the printhead cleaning procedure. See 
Maintaining the printheads.
Turn off the printer after removing the printhead
▲After removing the printhead, turn off the printer, wait about 20 seconds, and turn it on again
without the printhead installed. After the printer has restarted, reinsert the printhead.
Printer takes a long time to print
Check the system configuration
▲Make sure the computer meets the minimum system requirements for the printer. See 
System
requirements.
ENWW Resolving printing problems 41
 
						

							Check the printer software settings
▲The printer prints slower when Best or Maximum dpi is selected as the print quality. To increase
the print speed, select different print settings in the printer driver. See 
Changing print settings.
Check for radio interference
▲If the printer is connected using wireless communication and is printing slowly, then the radio
signal might be weak. See 
Guidelines for reducing interference on a wireless network.
Blank page printed
Check for empty ink cartridges
▲Check the printer lights to see which cartridge is low (see 
Interpreting control panel lights). The
Toolbox (Windows), HP Printer Utility (Mac OS), and the configuration page (see 
Understanding
the configuration page) provide information about ink levels. If you are printing black text and a
blank page prints, the black cartridge might be empty. See 
Replacing the ink cartridges.
Check the media settings
●Make sure you select the correct print quality settings in the printer driver for the media loaded in
the trays.
●Make sure the page settings in the printer driver match the page size of media loaded in the tray.
Something on the page is missing or incorrect
Check the printheads
▲Print the print quality diagnostic page on a clean sheet of white paper. Evaluate any problem
areas, and perform the recommended actions (see 
To print the print quality diagnostic page).
Check the margin settings
▲Make sure the margin settings for the document do not exceed the printable area of the printer.
See 
Setting minimum margins.
Check the color print settings
▲Make sure Print in Grayscale is not selected in the printer driver.
Check the printer location and length of USB cable
▲High electromagnetic fields (such as those generated by USB cables) can sometimes cause
slight distortions to printouts. Move the printer away from the source of the electromagnetic
fields. Also, it is recommended that you use a USB cable that is less than 3 meters (9.8 feet)
long to minimize the effects of these electromagnetic fields.
Placement of the text or graphics is wrong
Check how the media is loaded
▲Make sure the media width and length guides fit snugly against the edges of the stack of media,
and make sure the trays are not overloaded. See 
Loading media.
42 Chapter 4   Maintaining and troubleshooting ENWW