I’ve noticed in OS X Yosemite (10.10.1) that my Brother MFC-7820N no longer seems to have OS-level support for scanning.
If I look in “Image Capture”, the scanner is not listed under shared devices and if I look in the “Print Queue” window, the “Scanner Panel” window is unavailable; disabled in the Windows menu. Apple and Brother both still officially support this model with Yosemite.
I’ve tried manually installing the Brother 4.5.0 printer and scanner drivers from the Brother web site, just in case the problem had something to do with the automatic installation from Apple. The Brother drivers include the “Control Center” utility and I can scan just fine using that, so the scanner does seem to be working.
I’m at something of a loss on how to even try to diagnose this issue, since there aren't any error messages I'm receiving.