iMac no longer prints to Brother HL-5470DW printer after Yosemite upgrade
I upgraded my iMac 21.5" (late 2012) to OS X Yosemite (10.10.4) this week, and have found that I can no longer wirelessly print to my Brother HL-5470DW printer. When I go to print a file, it appears to spool properly, but nothing happens--the printer remains in it's 'sleep' mode. When I press 'GO' on the printer, it wakes and goes to 'pause' because no data is there to print from. When I open the print queue, I see that my document is ready and waiting to print, but the printer never 'wakes up' from its sleep state. It looks like the computer can see and identify the printer on the network, but can't communicate with it. It only registers as "offline".
After spending an entire afternoon and evening scouring help sites, forums, and the Brother website, I have not found any working solutions. Here is a list of things I've already tried:
Deleting the printer from System Preferences, restarting, then adding it again, with an updated driver
Using Disk Utility to Repair Permissions, restarting, adding the updated driver
Deleting the Brother folders from the hard drive's Library and Cache folders, restarting, then updating driver
Adding the printer using its IP address instead of via Bonjour (didn't work...but maybe I missed a step somewhere on that one)
Rebooted the printer (I checked and the printer is connecting to the network just fine. And my MacBook Pro can still print to it, as can a pair of Dell laptops.)
I didn't try downloading a prior driver (like for OS X 10.9 for example), but would need some detailed instructions on every step of implementing that.
Also, I did find a firmware update from Brother, but since my iMac can't communicate with the printer, it couldn't send the firmware update either. The update says it requires a special Java tool to function, too. I might try using my MacBook Pro to send it, though. But I'm going to try that tomorrow. I'm done for tonight.
Thanks in advance if anyone out there has the silver bullet for this particular problem.
iMac (21.5-inch, Late 2012), OS X Yosemite (10.10.4), Brother HL-5470DW printer