A yellow line or streak on printed documents from an HP printer can be caused by various issues, including a dirty printhead, a faulty ink cartridge, or paper feed problems. Here are some steps to help you troubleshoot and fix the issue:

Inspect the Printed Page: Examine the printed page carefully to determine the location and width of the yellow line. This information can help pinpoint the cause of the problem.

Clean the Printhead: Over time, the printhead can accumulate dried ink or debris, leading to streaks or lines on the printout. Many HP printers have a printhead cleaning utility in their settings or on the control panel. Run the printhead cleaning process to see if it resolves the issue. Refer to your printer’s user manual for specific instructions on how to clean the printhead.

Check the Ink Cartridges:

• Ensure that the yellow ink cartridge is correctly install in its slot. Make sure it’s securely snapped into place.
• Check the ink level in the yellow cartridge. If it’s low or empty, replace it with a new one.
• Sometimes, ink cartridges can become clogged or dried out. If cleaning the printhead doesn’t work, you may need to clean or replace the yellow ink cartridge.

Use Genuine HP Ink Cartridges: Using genuine HP ink cartridges is crucial for optimal print quality. Non-genuine or refilled cartridges can sometimes cause printing problems.

Check Paper Quality and Loading:

• Ensure that you are using the correct type and size of paper recommended for your printer.
• Check the paper tray for any misaligned or curled paper. Straighten or replace any damaged paper.
• Ensure that the paper guides in the tray are properly adjusted to hold the paper in place.

Update Printer Drivers: Outdated or incompatible printer drivers can sometimes lead to print quality issues. Visit the HP website and download the latest printer drivers for your specific model.

Run a Print Quality Diagnostic Test: Many HP printers have built-in diagnostic tests that can help identify and resolve print quality issues. Refer to your printer’s user manual for instructions on how to run a print quality test.

Clean the Printer Rollers: Dirty or worn-out printer rollers can cause streaks or lines on printed pages. Use a lint-free cloth lightly dampened with water to clean the rollers. Be sure they are completely dry before using the printer again.

Inspect the Imaging Drum (for Laser Printers): If you have an HP laser printer, inspect the imaging drum for any damage or contamination. If necessary, replace the imaging drum following the manufacturer’s guidelines.

Contact HP Support: If none of the above steps resolve the issue, or if you suspect a hardware problem, it’s advisable to contact HP Printer Technical Support UK or a certified technician for further assistance. They may be able to diagnose and repair the problem or provide additional guidance.

Keep in mind that printer maintenance and troubleshooting can vary depending on the specific model of your HP printer. Always refer to your printer’s user manual or visit HP’s official support website for model-specific instructions and troubleshooting resources.