Brother HL 1240 - B/W Laser Printer Service Manual page 93

(5) Disconnect the 11 (eleven) connectors for HL-1240 or 12 (twelve) connectors for HL-1250
from the engine PCB to remove the engine PCB ASSY.
Main PCB connector
Low-voltage power
supply connector
Thermistor connector
Fan motor connector
Polygon motor connector
!
CAUTION:
·
Even if you want to remove only one of either the engine and high-voltage power supply
PCBs, ensure you remove all screws securing both PCBs and disconnect the central
connector while lifting both of them up. Failure to do may damage the PCBs.
·
When re-assembling the engine PCB, ensure it is aligned with the positioning boss first.
Be careful the main motor harness is not caught between the engine PCB and the frame.
·
When re-assembling the engine PCB or high-voltage power supply PCB, ensure the
central connector is connected correctly.
Low-voltage power
Toner sensor (light
supply connector
reception) connector
(for HVPS)
Solenoid connector
Panel PCB
connector
Fig. 4-51
4-29
CHAPTER 4 DISASSEMBLY AND RE-ASSEMBLY
Engine PCB ASSY
Toner sensor (light
emission) connector
Main motor connector
Lower paper cassette
connector (HL-1250 only)