My laptop is macbook pro with the system macOS Sierra 10.12.6.
Begining the summer, about July 2017, when I want to print a PDF by the application Preview from Airprint, the black ink does not work. If the document has multi-colored, only the black is missing. All the settings are defaults.
However, if I change the setting of media type from "Auto Select" to "Photo", the printer can print same PDF as normal.
I have no idea about the printer or my laptop. I try to reset all the settings of printer and the mac. Not work.
And I also try to use a windows laptop to print several documents like PDF, word. Same situation, no black.
So can anybody help me to fix it? Now, I cannot use my smartphone to print directly or other method to print by laptop.
Thank you very much