Brother HL-4140CN Service Manual page 260

(15) Disconnect the wiring of the MP paper empty/registration front sensor PCB ASSY.
(16) Remove the Taptite bind B M3x8 screw, and then remove the MP paper empty/
registration front sensor PCB ASSY from the MP upper cover ASSY.
MP paper empty/registration
front sensor PCB ASSY
Harness routing: Refer to
Taptite bind B M3x8
Fig. 3-150
" MP Paper Empty/Registration Front Sensor PCB ASSY"
3-112
MP upper cover ASSY
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