Tray 1 solenoid ........................................................................................

34

Duplex solenoid .......................................................................................

35

Motors and fans ......................................................................................................

37

Main motor .............................................................................................

37

Fan ........................................................................................................

39

Printed circuit-board assemblies (PCAs) ......................................................................

41

Engine controller assembly (DC controller) PCA ............................................

41

Universal serial bus (USB) PCA ..................................................................

46

Formatter PCA .........................................................................................

48

Wireless PCA ..........................................................................................

48

Power switch PCA ....................................................................................

49

Connecting PCA ......................................................................................

51

Miscellaneous parts .................................................................................................

52

Transfer roller ..........................................................................................

52

Multipurpose (MP) tray pickup gear assembly ..............................................

52

Optional paper feeder (Tray 3) .................................................................................

53

Optional paper feeder right cover ..............................................................

54

Optional paper feeder driver PCA ..............................................................

54

Optional paper feeder paper sensor PCA ...................................................

55

2 Parts and diagrams ........................................................................................................

59

Order parts by authorized service providers ..............................................................................

60

Order replacement parts ..........................................................................................

60

Related documentation and software .........................................................................

60

Supplies part numbers .............................................................................................

60

Whole-unit replacement part numbers ........................................................................

60

How to use the parts lists and diagrams ....................................................................................

62

Assembly locations .................................................................................................................

63

HP LaserJet M401a, M401n, M401d models .............................................................

63

HP LaserJet M401dn and M401dw models ................................................................

64

Optional paper feeder .............................................................................................

65

Covers, panels, and doors ......................................................................................................

66

Internal assemblies .................................................................................................................

70

Input devices .........................................................................................................................

82

500-sheet paper feeder ...........................................................................................

82

Paper feeder covers ..................................................................................

82

Paper feeder main body (1 of 2) ................................................................

84

Paper feeder main body (2 of 2) ................................................................

86

Alphabetical parts list .............................................................................................................

88

Numerical parts list ................................................................................................................

93

vi

ENWW