advised by hp to repace printheads carriage won't go to centre web page says this means they don'

[MTP30]

advised by hp (on phone) to replace printheads carriage won't go to centre web page says this means they don't need replacing . The black is scrappy lots missing despite printing repeatedly and no black comes out in colour printing so all a colourful mess

[Echo_Lake]

@MTP30

Thank you for posting on the HP Support Community.
 

Don't worry as I'll be glad to help,
I appreciate your efforts to try and resolve the issue. This seems like a hardware issue with the printer. 

If you have already performed the steps from the document Print head Errors: https://support.hp.com/in-en/document/c04100778 and the issue persists, it could be a hardware failure. I'm sending out a private message to assist you with the next course of action. Please check your Private message icon on the upper right corner of your HP Community profile Next, to your profile Name, you should see a little blue envelope, please click on it or simply click on this link: https://h30434.www3.hp.com/t5/notes/privatenotespage
 

Hope this helps! Keep me posted for further assistance.
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