Scan unable AF error message

Had this exact error on my 5-month old MFC-J985DW immediately after using my auto feeder to scan a 2-paged doc for the first time (unsuccessfully) I had to install the Brother Utilities / Content Control 4 to scan so just prior to the symptom appearing I had installed those new apps to operate the printer and used the AF for the first time. My printer just cycled back to "Scan Unable AF" when I pressed the red X or cycled power. Unable to print,copy, scan. Printer was completely unusable and all web articles indicated that the problem was mechanical and that service by a tech would be required.

What seemed to fix it was when I lifted the left door of the document feeder and rocked the rollers back and forth, actuated the mechanisms I could find and then, when the printer reinitialized, it threw an error stating that it ?couldn't identify any of my cartridges? I then reseated the ink cartridges, they were successfully identified and the printer announced that a Firmware Update was found and prompted me to update; which I did. After that the printer has worked perfectly. I should mention that I had called Brother support and they left me on hold for 20 minutes before disconnecting me. They had the machine SN and I suppose they could have also sent a reset to the printer or pushed the firmware prompt without my knowledge. I think that when I shook a bind or spec of paper loose on the AF roller, the new Firmware version that was compatible with the apps I installed to use the scanner fixing a sw incompatibility, or Brother pushed a reset to the printer before disconnecting. Good luck.