HP LaserJet Pro MFP M521 - Fax; Set up the product for fax; Configure send fax settings; Configure receive fax settings

Developing stage ..................................................................................... 29
Toner cartridge ......................................................................... 29
Transfer stage .......................................................................................... 30
Fusing stage ............................................................................. 30
Cleaning stage ......................................................................... 31
Toner detection ....................................................................................................... 32
Pickup, feed, and delivery system ............................................................................................. 33
Paper trays ............................................................................................................. 33
Photo sensors and switches ...................................................................................... 34
Solenoids and clutches ............................................................................................ 36
Tray 1 or Tray 2 .................................................................................................................... 38
Pickup and feed unit ................................................................................................ 38
Cassette paper size detection/cassette paper detection ................................ 38
Cassette pickup ........................................................................................ 38
Tray 1 paper pickup ................................................................................................ 38
Paper pickup and feed ............................................................................................ 39
Jam detection ......................................................................................................... 40
Additional tray ...................................................................................................................... 41
Tray driver PCA ...................................................................................................... 41
Paper pickup and feed ............................................................................................ 42
Paper level and size detection .................................................................................. 43
Jam detection ......................................................................................................... 43
Scanner system ...................................................................................................................... 44
Scanner power-on sequence of events ....................................................................... 44
Copy or scan sequence of events .............................................................................. 45
2 Solve problems ............................................................................................................... 47
Solve problems checklist ......................................................................................................... 48
Menu map ............................................................................................................................ 50
Troubleshooting process .......................................................................................................... 51
Pre-troubleshooting checklist ..................................................................................... 51
Determine the problem source ................................................................................... 52
Troubleshooting flowchart ......................................................................... 52
Power subsystem ..................................................................................................... 53
Power-on checks ...................................................................................... 53
Power-on troubleshooting overview .............................................. 53
Control-panel checks ............................................................................................... 54
Tools for troubleshooting ......................................................................................................... 56
Diagrams ............................................................................................................... 56
Block diagrams ........................................................................................ 56
Location of connectors .............................................................................. 58
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