User Guide

Motor and fan control
The HP LaserJet 4200 Series printers contain three dc brushless motors: the main motor, the lifter-
driver motor (inside of the lifter-driver assembly), and a fan motor. The main motor is used for image
formation (rotating the photosensitive drum in the print cartridge) and paper pickup and feed. The
lifter motor raises the plate in the tray cassette. The fan motor rotates the fan blades.
The HP LaserJet 4250, 4300, and 4350 Series printers contain five dc brushless motors: the main
motor, the print cartridge motor, the lifter motor, and two fan motors. The main motor is used for
paper pickup and feed. The print cartridge motor rotates the photosensitive drum. The lifter motor
raises the plate in the tray cassette. Two fan motors rotate the left- and right-side fans.
Table 5-2 Printer fans and motors
Component Purpose Type Rotation Speed
Main motor (M101),
HP LaserJet 4200 and
4200L Series printers
Drives the tray cassette pickup
roller, feed/separation roller, tray 1
pickup roller, pre-transfer roller,
photosensitive drum, developing
cylinder, pressure roller, and output
delivery roller
Dc Counterclockwise Two-speed (full-
and half-speed)
Main motor (M101),
HP LaserJet 4250, 4300,
and 4350 Series printers
Drives the tray cassette pickup
roller, feed/separation roller, tray 1
pickup roller pre-transfer roller,
pressure roller, and output delivery
roller.
Dc Counterclockwise Two-speed (full-
and half-speed)
Print cartridge motor
(M102),
HP LaserJet 4250, 4300,
and 4350 Series printers
Drives the transfer charging roller,
photosensitive drum, and
developing cylinder.
Dc Counterclockwise Two-speed (full-
and half-speed)
Lifter motor (M103), all
printer models
Moves the tray cassette lifting plate
up and down.
Dc Counterclockwise Single-speed
Left-side cooling fan
(FN101), all printer models
Cools the inside of the printer Dc NA Two-speed (full-
and half-speed)
Right-side cooling fan
(FN102),
HP LaserJet 4250, 4300,
and 4350 Series printers
Cools the inside of the printer. Dc NA Single-speed
General descriptions 109