Canon BJC 3000 Reference Manual page 181

Check 1
Grayscale Print selected?
Open the Printer Properties dialogue box and disable Grayscale Print in the
Windows
Main tab.
Disable Print Grayscale on the left bottom corner of the Print dialogue box.
Macintosh
Check 2
Monochrome printing selected in application program?
Some application programs have a setting in its print dialogue box that
allows you to enable or disable colour printing.
Check that the setting is enabled in the application program.
For details, refer to the documentation of the application program.
Colour document printed in monochrome
Troubleshooting - Printout is Unsatisfactory 181