Step 6: secondary transfer...................................................................................96
Step 7: separation................................................................................................97
Fusing stage.........................................................................................................................98
Step 8: fusing.......................................................................................................98
Step 9: roller charging (auxiliary transfer belt cleaning roller).............................98
Step 10: roller charging (transfer-belt cleaning roller).........................................99
Step 11: transfer belt cleaning.............................................................................99
Step 12: drum cleaning......................................................................................100
Print cartridge......................................................................................................................102
Imaging-drum E-label.........................................................................................................103
Scanner and ADF functions and operation.........................................................................................104
Scanner functions ..............................................................................................................104
Scanner operation...............................................................................................................104
ADF operation.....................................................................................................................105
ADF paper path and ADF sensors.....................................................................................105
ADF jam detection..............................................................................................................106
Fax functions and operation................................................................................................................107
PSTN operation..................................................................................................................107
To receive faxes when you hear fax tones.........................................................................107
The fax subsystem..............................................................................................................107
Formatter in the fax subsystem..........................................................................................108
LIU in the fax subsystem....................................................................................................108
Safety isolation...................................................................................................108
Safety-protection circuitry...................................................................................108
Data path............................................................................................................109
Hook state..........................................................................................................109
Downstream current detection...........................................................................109
Hook switch control............................................................................................109
Ring detect.........................................................................................................110
Line current control............................................................................................110
Billing (metering) tone filters..............................................................................110
Fax page storage in flash memory.....................................................................................110
Stored fax pages................................................................................................111
Advantages of flash memory storage ...............................................................111
5 Removal and replacement
Chapter contents.................................................................................................................................113
Removal and replacement strategy ....................................................................................................114
Required tools.....................................................................................................................114
Screws................................................................................................................................114
Electrostatic discharge........................................................................................................115
Before performing service...................................................................................................116
After performing service......................................................................................................116
Post-service tests................................................................................................................116
Test 1 (print-quality test)....................................................................................116
Test 2 (copy-quality test)....................................................................................117
Test 3 (fax-quality test).......................................................................................117
Test 4 (memory-card test)..................................................................................117
Parts removal order............................................................................................................118
User-replaceable parts........................................................................................................................119
vi ENWW