Brother DCP-J552DW Service Manual page 202

Registration sensor PCB ASSY, inner chute ASSY and pressure roller release sensor PCB
ASSY
(The pressure roller release sensor PCB ASSY is present only in disc printing models.)
(6) Press down the lock arm boss part of the chute cover, remove it from the opening in the CR
guide rail, and remove the chute cover by sliding it to the right (to the left if you are looking
from the rear) and releasing the four locks.
Lock arm boss part
(Rear)
Chute cover
Lock
3-85
CR guide rail
Lock
(3_110)
Confidential