So I recently picked up a Firepower 4110 from work to test various things for a customer. Unfortunately, I could not get the management interface to come up. The show commands seemed to show that it was admin down.
!! Will add diagnostic information later. -jay 2/1/2018
Remove all optics from FP4110 chassis.
Unplug chassis for 15 minutes.
Plug in chassis. Wait for bootup.
Insert GLC-T (Not GLC-TE, SPF-GLC-T, GLC-SX-MMD, or any other optics) into Management Port (next to console port)
Attempt to connect to Firepower Chassis Manager (FCM).