We have been getting white horizontal lines on our documents. Both print heads were recently replaced and that did not solve the problem. What part is needing replaced?
I had this same problem and none of the printer services (clean printhead, align printer, calibrate linefeed) fixed the problem. After trying every solution that I found on the internet with no success I was able to fix the problem by cleaning two critical parts of the printer.
1. Turn off the printer and open it as though you are going to change the printheads.
2. Towards the back of the printer you will see a thin clear plastic ribbon that has very small black lines on it. Very, very, very gently clean this ribbon. I used a lint free cloth and some glass cleaner. Spray the cleaner on the cloth and slide the cloth against both sides of the ribbon. Do not pull on the ribbon. This ribbon is used to tell the printhead how far it has moved from side to side.
3. Next locate the silver bar that runs across the back of the printer. This bar is used to feed the paper through the printer as it is printing a document. On the left side of the bar you will see some plastic guides that hold the bar in place. On the outside of the plastic guides you should see a clear plastic disc made of the same material as the ribbon above. This disc also has very small black lines on it. Again very, very, very gently clean this plastic disc. This disk is used to tell the printheads how far it has travelled down the page. This is the one that was causing the problem. The dust or dried ink or whatever was on the disc was causing the printer to incorrectly calibrate the linefeed and was causing the white lines to appear on my documents.
4. Use the "calibrate linefeed" function of the printer services to recalibrate the linefeed and the white lines will hopefully be gone.
Jul 26, 2011 |
HP Officejet Pro L7780 All-In-One InkJet...