Brother HL-5440D Service Manual page 184

(3) Disconnect the registration front/rear sensor harness, the T1 paper feed sensor harness
and the MP paper empty sensor harness from the high-voltage power supply PCB
ASSY, and remove the high-voltage power supply PCB ASSY from the machine.
(4) Disconnect the main HVPS flat cable from the high-voltage power supply PCB ASSY.
Harness routing: Refer to
Fig. 3-66
"4.High-voltage power supply PCB
3-65
MP paper empty sensor harness
T1 paper feed sensor harness
Main HVPS flat cable
Registration front/rear sensor harness
High-voltage power supply PCB ASSY
ASSY".
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