We also have this same issue with my Canon ImageCLASS MF216n that we bought about 3 weeks ago. The printer is connected by static IP to the network. It is not located in a place where everyone can go and press the Eco mode button which is WHY we wanted a network-ready printer..
I have been in contact with your support people. They answered my first message but have ignored me ever since which I find to be totally unprofessional.
I need to learn how to:
(1) disable it from going into "sleep" mode, or
(2) have a way to wake it, programmatically..
At this time the only way to wake it is to power down, then power back up. Isn't that ridiculous?
Thank you.