I am using macOS Mojave 10.14.6 with my Workcentre 6515 and it does not communicate with the scanner when I try to access the scanner through the Printers & Scanners app from the System Preferences. I get a message that it is waiting for the scanner and does not wake up the scanner. On a second mac using macOS High Sierra 10.13.6, I can get the scanner to operate. I have downloaded and installed all the newest drivers and firmware on the Workcentre 6515 and still cannot get the scanner to respond.