Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
Please do a test photocopy with your printer, using the printer's own controls and buttons: just photocopy one page in full color with some black in it, and see how much of the colors come out in the photocopy, please.
Also, what Windows PC (or Apple computer) do you have, that you print with? in case it matters, RE the instructions I am about to give you.
Are you using HP OEM-original inks? not refills, remanufactured cartridges, nor 'HP Compatible' cartridges?
I think you should try a certain cleaning procedure that I have found effective, first.
1. Clean the (black) printhead. (This is a Maintenance function that you can perform from the printer's menu or from the software on your HP laptop computer... if you need instructions, just ask.)
2. Wait 1/2 hour to several hours or overnight, leaving the printer On but unused (no print jobs, etc.)
This allows waste ink to soak into the printhead and hopefully dissolve dried ink etc.
3. Clean the printhead a second time.
4. Wait again (as in step 2 above) for 1/2 hr. to several hrs., printer On but unused.
5. Clean the printhead a third time.
Then test whether black ink is showing up at all in prints at this point. If it is, even faintly, then repeating this procedure will (eventually, at the cost of a certain amount of ink wasted in the process) clear up the clogged printhead.
After that fails, if it does fail, what you need to do is to decide whether replacing the printhead (which will cost something considerable, more than you would think usually) is better, given the printer's age, or whether it would be more preferable for you to replace the printer altogether with a new one (and hopefully recycle the old printer, always a good idea.)
So try the triple-cleaning-with-wait-times that I recommended, and get back to me if it doesn't work for you (so I can advise you further...)... or if it does help (- I always like to hear that something I recommended has worked!)
Just come back to this link, which is the page reserved for your current question:
and let me know how it has gone. Thanks.