Why my printer doesn't print color gray?

[Eastern_Dude]

Hi.

I have a HP Photosmart c4780 all-in-one printer.

I have two very little used original cartridges, one black and one color. Maybe I bought them 10 or 11 months ago and I rarely used them, I think I printed with them less than 10 times. I only printed two certificates and a few documents more.

I drew a piece of furniture in a software, and the pdf version has a box of gray color, also the dimensions are in gray color. The document was opened in adobe reader. The printer didn't print the gray color, it was empty, I mean, it was white as paper. Only the figure with its black lines printed well.

I tried to print some texts as a test in Word, one paragraph in black, one in blue, one in red and one in gray.

Only the paragraph in black was well printed, the others were white.

Again, I changed the measurements color from gray to black and I opened them in adobe reader again and the figure and the measurements were well printed in black, but the box with gray lines didn't and I selected this time the checkmark "print in grayscale".

Why my printer is not printing gray lines?

Also, my ink levels are at a good level, so, the fact that it isn't printing in color, and not printing the gray color with print in grayscale option, is very odd.

Thank you.

[Kumar0307 · Accepted solution]

@Eastern_Dude, Welcome to the HP Support Community!

Have you tried using alternate ink cartridges and check if the issue persists?

You may experience this issue if the ink has dried up in the color ink cartridge. Let us try these steps to resolve this issue:

Use an automated tool to clean the cartridges

Open HP Solution Center:

1. Click Settings ().

2. In the Print Settings area, click Printer Toolbox. The printer Toolbox opens.

3. On the Device Services tab, click Clean the Print Cartridge(s) ().

4. Click Clean to begin the process.

Clean the area around the nozzles

1. Set the cartridge on a piece of paper with the ink nozzles facing up.

2. Lightly moisten a clean, foam-rubber swab with distilled water.

3. Clean the face and edges around the ink nozzle with the swab.

      CAUTION: 

   Do not clean the ink nozzle plate.

   Figure : Clean the area around the ink nozzle

4.  

1. Nozzle plate - DO NOT CLEAN

2. Area surrounding ink nozzle - Do clean

3. Cartridge contacts - Do not clean

For more info on resolving print quality issues, refer to this document.

Hope this helps! Keep me posted. 

Please click “Accept as Solution” if you feel my post solved your issue, it will help others find the solution.

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