Brother HL-L9300CDW Service Manual page 360

(19) Release the five Hooks and remove the Toner filter ASSY from the Paper eject ASSY.
Toner
filter ASSY
Hook
(20) After replacing the Fuser unit, reset the counter.
(Refer to "1.3.29 Reset counters for parts (Function code 88)" in Chapter
Hook
Fig. 7-17
7-11
Paper eject ASSY
Paper eject ASSY
Hook
5.)
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