Colour cartridges are still required to be present but can be set to not be used. If grayscale is selected the printer will still use some colour ink to enhance the black (called rich black). If you set it to black & white only or black only, it won't use this, but can result in black being more like a dark grey instead. See https://support.hp.com/nz-en/document/c05078948 for info.
Answered by: PB Tech on 29 April 2020