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HP Smart Tank 450 Printers - A Blinking 'P' Error Displays

This document is for HP Smart Tank Wireless 450, 455, and 457 printers.
After installing the printheads, the printer displays a blinking P from the control panel, which indicates that you can start the ink priming process. Before starting the priming process, make sure all the ink tanks are full, the printheads are installed correctly, and paper is loaded in the input tray.

Step 1: Make sure the ink tanks are full

Before you start the priming process, make sure there is enough ink in every tank. The ink levels should be within the maximum and minimum fill lines on the ink tank.
    Figure : Example of properly filled ink tanks
  1. Maximum fill line
  2. Minimum fill line

Step 2: Make sure the printheads are properly installed

Install the printheads properly. If you have already installed the printheads, skip to the next step.
Do not open the blue carriage latch after printhead installation unless you are installing new printheads or moving the printer long distances.
Do not open carriage latch
  1. With the printer turned on, open the exterior door, and then open the printhead access door.
    The printhead carriage moves to the center of the printer.
    Figure : Accessing the printhead carriage
    Image: Access the printhead carriage
  2. Install the printheads.
    • Insert the black printhead into the right slot.
    • Insert the tri-color printhead into the left slot.
    Figure : Inserting the black and color printheads
    Image: Insert the printheads
  3. Close the blue carriage latch by pushing down firmly until the latch snaps into place.
    Figure : Closing the blue carriage latch
     Closing the latch

Step 3: Load paper

Load plain white paper in the input tray.
  1. Raise the input tray.
    Image: Pull up the input tray
  2. Slide the paper width guide all the way to the left.
    Image: Slide the paper width guide left
  3. Load plain white paper into the input tray, slide the stack of paper down until it stops, and then slide the paper width guide against the edge of the paper.
    Image: Load paper and slide guide right
  4. Pull out the output tray, and then raise the tray extender.
    Image: Pull out the output tray and tray extender

Step 4: Confirm that the printer can start the printing process

After you verify that there is sufficient ink in the tanks, the printhead is latched, and paper is loaded, align the printer and then start the priming process.
  1. On the printer control panel, press and hold the Resume button for 3 seconds to start the priming process.
    The printer prints an alignment page.
    The alignment page might have a small blot or smear at the bottom of the page. This is a normal during the printer's initial setup.
    Figure : Pressing and holding the Resume button
    Press and hold the resume button
  2. Lift the scanner lid.
  3. Place the alignment page with the print side down on the right-front corner of the scanner glass, and then close the scanner lid. Position it according to the guides around the scanner glass.
    Figure : Placing the alignment page on the scanner glass
    Printer alignment
  4. Close the scanner lid.
  5. On the control panel, press the Start Copy Color button .
    The printer aligns the printheads.
    Alignment is complete when the A becomes a 0 on the control panel.
    Figure : Alignment complete
    Alignment complete






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