Welcome to Nick's Random Musings

Sent from my radio telephone.

The Canon MF733 is a nice, reliable, economical printer, but it’s really annoying that out of the box it complains about empty toner at 20% levels.

To turn that down or off entirely, go into:
Menu -> Preferences -> Display Settings -> Display Timing for Cart. Prep ON/OFF.

Enter toner level in Custom level and hit apply.