HP Laserjet P4015X prints black pages

Hi, I have got a HP Laserjet P4015X and it prints black pages exactly the same as in this post for the P1006

http://h30434.www3.hp.com/t5/Printer-All-in-One-Install-Setup/HP-Laserjet-P1006-Printing-BLACK-pages-problem/td-p/1848463

I have tried another toner and checked the contacts on the printer that connects to the toner. I have also installed a new maintenace kit.

Hope I am missing something, please help

Thank you