Brother HL-4040CN, HL-4050CDN, HL-4070CDW Service Manual page 175

(2) Disconnect the Connector (CN35) from the Engine PCB ASSY.
(3) Remove the one cup S M3x6 Taptite screw, and then remove the THM/HUM ground plate.
(4) Remove the four cup S M3x6 Taptite screws.
(5) Release the two Hooks to remove the THM/HUM sensor holder ASSY.
Hook
THM/HUM sensor
holder ASSY
Taptite, cup S M3x6
THM/HUM ground plate
Taptite, cup S M3x6
CN35
Fig. 3-80
Frame unit
Hook
<Left side>
Fig. 3-81
3-66
Engine PCB ASSY
Confidential