Brother HL-4040CN Service Manual page 210

(6) Remove the six bind B M4x12 Taptite screws, and then remove the Drum drive ASSY from
the Frame unit.
Note:
Since the four Gears 39/121 of the Drum drive ASSY are assembled together, which
makes one set, DO NOT replace only one gear. If their replacement is required, replace
the complete Drum drive ASSY.
Gears 39/121
Taptite, bind B M4x12
Drum drive ASSY
Taptite, bind B M4x12
(7) Remove the bind S M3x6 Taptite screw, and then remove the Drum phase sensor PCB
ASSY 2 (whose harness is longer) from the Drum drive ASSY.
(8) Remove the Drum phase sensor PCB 1 (whose harness is shorter) in the same way.
Taptite, bind S M3x6
Drum phase sensor PCB ASSY 1
(whose harness is shorter)
<Left side>
Gears 39/121
Fig. 3-148
Positioning pin
Drum drive ASSY
Fig. 3-149
3-102
Frame unit
Taptite, bind S M3x6
Drum phase sensor PCB ASSY 2
(whose harness is longer)
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