Resolved Printer keeps waking up from sleep (SOLVED: It was the voicemail dial tone on the phone line)

[savoirfaire]

Hi, guys. I need some help. I have a Canon multi-function printer on my home network. For some reason, when my Mac (OS 10.13.4) is awake, the fan on the printer turns on briefly every couple of minutes and then clicks off again even though the printer is in sleep mode. I assume the Mac is pinging the printer for some reason. Is there a way I can stop this?

 

[BrianBaughn]

Have you logged into the printer's web portal to see if there are any errors?

 

[savoirfaire]

Actually, I was mistaken. After I put the Mac Pro to sleep this morning, a short time later, I heard the printer fan spinning up again even thought the Mac Pro was asleep. I pulled the Ethernet plug, and the fan still kept turning on periodically. Finally, I pulled the phone line that was plugged in to allow the unit to send/receive faxes, and it's been quiet for a few hours now. Seems odd that the phone line would be causing the printer to keep acting up, but tomorrow I will plug the phone line back in and see what happens...

 

[savoirfaire]

For anyone who runs into similar issues in the future, it turns out the problem was the phone/fax line after all. Whenever there is a voicemail causing there to be the interrupted dial tone rather than the continuous one, the printer gets confused and keeps thinking that there is an incoming call causing it to repeatedly wake up to listen for a fax tone.