CHAPTER III
To prevent the creation of secondary problems by mishandling, be careful about the
following precautions during maintenance work.
(1) Always turn off the power switch and unplug the power cord from the power outlet
before accessing any parts inside the printer.
(2) Be careful not to lose screws, washers, or other parts removed.
(3) Be sure to apply grease to the gears and applicable positions specified in this chapter.
(4) When using soldering irons or other heat-generating tools, take care not to damage
the resin parts such as wires, PCBs, and covers.
(5) Before handing the PCBs, touch a metal portion of the equipment to discharge the
static electricity charged in your body, or the electronic parts or components may be
damaged.
(6) When transporting PCBs, be sure to wrap them in conductive sheet such as aluminum
foil.
(7) Be sure to replace self-tapping screws correctly, if removed. Unless otherwise
specified, tighten screws to the following torque values.
TAPTITE, BIND or CUP B
M3 : 6kgf • cm
M4 : 9kgf • cm
TAPTITE, BIND S
M3 : 9kgf • cm
SCREW
M3 : 7kgf • cm
M4 : 10kgf • cm
(8) When connecting or disconnecting cable connectors, hold the connector bodies, but
not the cables. If the connector has a lock, release the connector lock first to unlock it.
(9) After a repair, check not only the repaired portion but also the connectors, or check if
other related portions are functioning properly before doing operation checks.
Summary of Contents for HL-720
Page 1: ...SERVICE MANUAL MODEL HL 720 730 730Plus R LASER PRINTER ...
Page 36: ...II 19 1 3 10 Engine I O HL 720 Fig 2 21 shows the engine interface circuit Fig 2 21 ...
Page 37: ...II 20 HL 730 730Plus Fig 2 22 shows the engine interface circuit Fig 2 22 ...
Page 61: ... Fig 3 18 2 4 1 1 1 ...
Page 92: ...SERVICE MANUAL MODEL HL 760 R LASER PRINTER ...
Page 109: ...II 8 1 3 4 DRAM Two 4M bit DRAMs x 16bits are used as the RAM Fig 2 6 ...
Page 113: ...II 12 1 3 10 Engine I O Fig 2 12 shows the engine interface circuit Fig 2 12 ...
Page 114: ...II 13 1 3 11 Paper Feed Motor Drive Circuit Fig 2 13 ...
Page 133: ...Appendix 2 Main PCB Circuit Diagram 1 3 CODE UK3227000 B48K272CIR 1 3 NAME ...
Page 134: ...Appendix 3 Main PCB Circuit Diagram 2 3 CODE UK3227000 B48K272CIR 2 3 NAME ...
Page 135: ...CODE UK3227000 B48K272CIR 3 3 NAME Appendix 4 Main PCB Circuit Diagram 3 3 ...