ImageClass MF743CDW becomes unresponsive in MacOS

[jwalters]

Hi,

I have an ImageClass MF743CDW that prints great, but has a really annoying habit of becoming unresponsive in our Mac/iOS dominated house.  The basic issue is that the printer will work fine for awhile, then one or both Macs running MacOS Mojave will suddenly be unable to communicate with the printer.  So far the solution has been to delete the printer from the print queue, reinstall the printer, hope that it finds all of the functions (which doesn't always happen) then print for a period of minutes, days or weeks and repeat.  In fact, as I write this, I set up the printer about 20 minutes ago and MacOS is already unable to print to it, after doing so once and scanning once.  The symptom is always the same, the print queue is stuck "looking for printer."  

It's becoming rather annoying.  I've reset the entire print subystem with no improvement.  Is there any solution to this problem?

[shadowsports]

Greetings,

How are these devices communicating?

Based on your description, it sounds like the printer and Macs are connected to the same network?

Does the printer show as "offline" when you cannot print to it?

3 things come to mind.

-Drivers issue

-Issue with your router, AP or network configuration

or

-The printer is not waking or coming out of sleep when a print job is sent

A few steps you can perform to troubleshoot:

Drivers:

First step.  Confirm the drivers you are using are correct for the MAC OS you have installed.  If you upgraded the OS from an earlier version using an earlier driver, confirm that driver is compatible with Mojave.  If unsure, you can download the Mojave drivers here:

Support | Color Laser | Color imageCLASS MF743Cdw | Canon USA

Network Configuration:

Don't rely on DHCP.  Assign the printer a static IP on your router.  After doing this you will need to restart the printer and ensure its using the assigned IP.

Then remove the printer from your MACs and resinstall the printer using its IP.  

Refer to this article:

Add a printer on Mac - Apple Support

Scroll down to the section on adding a printer by its IP.

Power Save or Sleep:

The last portion can probably be confirmed once you have ruled out the above 2 items.

You should always be able to ping another device on your network using its IP address if its turned on.  Once you have assigned a static IP to the printer, you can also open its webserver in a browser using that IP.

If the printer is not sleeping, see if you can ping it using terminal or open its web server in a browser.

If this works the printer is installed correctly and your network configuration is correct.  When the printer is asleep you can try pinging it again and opening its webserver in a browser.  If you can't look at the printers power save, sleep or ECO settings.

Hint: you can using the "moon" icon button onthe control panel to put the device to sleep for testing.

[jwalters]

Thanks for the follow-up.  It turns out that I'd addressed your suggestions, but that brought to mind another potential issue - wifi signal strength, or (potentially) flaky wifi support.  I've disabled the onboard wifi and ran an ethernet cable to see if that addresses the isues.  So far, several days in, things seem stable.