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HP LaserJet Pro - Resolving mono print quality problems

Use the information below to troubleshoot print-quality and image-quality problems on mono (black and white) HP LaserJet Pro printers.

Note:

For color HP LaserJet Pro printers, see HP Color LaserJet Pro - Resolving color print quality problems.

The troubleshooting steps can help resolve the following defects:

  • Blank pages

  • Black pages

  • Curled paper

  • Dark or light bands

  • Dark or light streaks

  • Fuzzy print

  • Gray background or dark print

  • Light print

  • Loose toner

  • Missing toner

  • Scattered dots of toner

  • Skewed images

  • Smears

  • Streaks

Troubleshoot print quality

To resolve print-quality issues, try these steps in the order presented.

To troubleshoot specific image defects, refer to the Troubleshoot Image Defects section further down in this document.

Troubleshoot image defects

Check the following table for the image defect that you are experiencing. Then click the link to learn more and find solutions.

Image defects, no matter the cause, can often be resolved using the same steps. Use the following steps as a starting point for solving image defect issues.

  1. Reprint the document. Print quality defects can be intermittent in nature or can go away completely with continued printing.

  2. Check the condition of the cartridge or cartridges. If a cartridge is in a Very Low state (it has passed the rated life), replace the cartridge.

  3. Make sure that the driver and tray print mode settings match the media that is loaded in the tray. Try using a different ream of media or a different tray. Try using a different print mode.

  4. Make sure that the printer is within the supported operating temperature/humidity range.

  5. Make sure that the paper type, size, and weight are supported by the printer. Supported paper types and sizes vary by printer model. To find the paper that is compatible with the printer, use these steps to navigate to the HP product support page for the printer and view the Product Information section.

    1. Go to support.hp.com, type the printer model in the text field, and then click Submit.

    2. Scroll to and click Product Information.

    3. In the Select a topic drop-down menu, click Compatibility, and then click Supported paper sizes and types.

The following examples depict letter-size paper that has passed through the printer short-edge first.

Banding

Sample

Description

Possible solutions

Dark or light lines

Dark or light lines which repeat down the length of the page, and are wide-pitch and/or impulse bands.

They might be sharp or soft in nature. The defect displays only in areas of fill, not in text or sections with no printed content.

  1. Reprint the document.

  2. Try printing from another tray.

  3. Replace the cartridge.

  4. Use a different paper type.

  5. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Black page

Sample

Description

Possible solutions

Black page

The entire printed page is black.

  1. Visually inspect the cartridge to check for damage.

  2. Make sure that the cartridge is installed correctly.

  3. Replace the cartridge.

  4. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Blank page – No print

Sample

Description

Possible solutions

Blank page

The page is completely blank and contains no printed content.

  1. Make sure that the cartridges are genuine HP cartridges.

  2. Make sure that the cartridge is installed correctly.

  3. Print with a different cartridge.

  4. Check the paper type in the paper tray and adjust the printer settings to match. If necessary, select a lighter paper type.

  5. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Curled output

Sample

Description

Possible solutions

Curled pages

Printed pages have curled edges. The curled edge can be along the short or long side of the paper. Two types of curl are possible:

  • Positive curl: The paper curls toward the printed side. The defect occurs in dry environments or when printing high-coverage pages.

  • Negative curl: The paper curls away from the printed side. The defect occurs in high-humidity environments or when printing low-coverage pages.

  1. Reprint the document.

  2. Positive curl: From the printer control panel, select a heavier paper type. The heavier paper type creates a higher temperature for printing.

    Negative curl: From the printer control panel, select a lighter paper type. The lighter paper type creates a lower temperature for printing. Try storing the paper in a dry environment prior to use, or use freshly opened paper.

  3. Print in duplex mode.

  4. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Gray background or dark print

Sample

Description

Possible solutions

Dark text

The image or text is darker than expected and/or the background is gray.

  1. Make sure that the paper in the trays has not already been run through the printer.

  2. Use a different paper type.

  3. Reprint the document.

  4. Mono models only: From the Home screen on the printer control panel, go to the Adjust Toner Density menu, and then adjust the toner density to a lower level.

  5. Make sure that the printer is within the supported operating temperature and humidity range.

  6. Replace the cartridge.

  7. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Image placement defects

Sample

Description

Possible solutions

Skewed image

The image is not centered, or is skewed on the page.

This defect occurs when the paper is not positioned properly as it is pulled from the tray and moves through the paper path.

  1. Reprint the document.

  2. Remove the paper and then reload the tray. Make sure that all the paper edges are even on all sides.

  3. Make sure that the top of the paper stack is below the tray-full indicator. Do not overfill the tray.

  4. Make sure that the paper guides are adjusted to the correct size for the paper. Do not adjust the paper guides tightly against the paper stack. Adjust them to the indentations or markings in the tray.

  5. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Light print

Sample

Description

Possible solutions

Light print

The printed content is light or faded on the entire page.

  1. Reprint the document.

  2. Remove the cartridge, and then shake it to redistribute the toner. Reinsert the toner cartridge into the printer and close the cover.

  3. Mono models only: Make sure that the EconoMode setting is disabled, both at the printer control panel and in the print driver.

  4. Make sure that the cartridge is installed correctly.

  5. Print a Supplies Status Page and check the life and usage of the cartridge.

  6. Replace the cartridge.

  7. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Missing toner on edge

Sample

Description

Possible solutions

Toner rubs off

Toner rubs off along either edge of the page.

This defect is more common at the edges of high-coverage jobs, and on light media types, but can occur anywhere on the page.

This issue occurs during the "fixing" or "fusing" part of the printing process where toner is affixed to the paper.

  1. Reprint the document.

  2. Check the paper type in the paper tray and adjust the printer settings to match. If necessary, select a heavier paper type.

  3. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Repeated shadows or offsets

Sample

Description

Possible solutions

Shadows or offsets

Slight shadows or offsets of the image are repeated down the page. The repeated image might fade with each recurrence.

This issue occurs during the "fixing" or "fusing" part of the printing process where toner is affixed to the paper.

  1. Reprint the document.

  2. Check the paper type in the paper tray and adjust the printer settings to match. If necessary, select a lighter paper type.

  3. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Stacking defects

Sample

Description

Possible solutions

Skewed output stack

The paper does not stack well in the output tray. The stack might be uneven, skewed, or the pages might be pushed out of the tray and onto the floor.

Any of the following conditions can cause this defect:

  • Extreme paper curl

  • The paper in the tray is wrinkled or deformed

  • The paper is a non-standard paper type, such as envelopes

  • The output tray is too full

  1. Reprint the document.

  2. Extend the output bin extension.

  3. If the defect is caused by extreme paper curl, refer to the troubleshooting steps for "Curled output."

  4. Use a different paper type.

  5. Use freshly opened paper.

  6. Remove the paper from the output tray before the tray gets too full.

  7. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Streaks

Sample

Description

Possible solutions

Vertical streaks

Light vertical streaks that usually span the length of the page. The defect displays only in areas of fill, not in text or sections with no printed content.

  1. Reprint the document.

  2. Remove the cartridge, and then shake it to redistribute the toner. Reinsert the toner cartridge into the printer and close the cover.

  3. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Note:

Both light and dark vertical streaks can occur when the printing environment is outside the specified range for temperature or humidity. Refer to your printer's environmental specifications for allowable temperature and humidity levels.

Vertical lines

Sample

Description

Possible solutions

Dark vertical lines

Dark vertical lines which occur down the length of the page. The defect might occur anywhere on the page, in areas of fill or in sections with no printed content.

  1. Reprint the document.

  2. Remove the cartridge, and then shake it to redistribute the toner. Reinsert the toner cartridge into the printer and close the cover.

  3. Print a cleaning page.

  4. Check the toner level in the cartridge.

  5. If the issue persists, refer to the Additional information section below for instructions on how to contact HP Customer Support.

Additional information

To find additional support and troubleshooting information for the printer, use the following steps to go to the HP product support page for the specific printer model.

  1. Go to support.hp.com, enter the printer model in the text field, and then click Submit.

    The product support page displays.

  2. Click a category (such as Troubleshooting, How to, or Product Information), and then use the drop-down menus to further narrow down the search to find support content on various topics.

If the information in this document did not help to resolve the issue, go to HP Customer Support to view the support options that are available, including a link to check the warranty status of the printer, or an option to sign-in if you have already registered for an HP account.

To contact customer support, start by clicking Printer in the list of product types, and then enter the printer's serial number for a list of contact options.