Xerox Phaser 840 Service Manual page 8

Troubleshooting
Network Event Logs ............................................................................................ 3 - 75
Electronics Troubleshooting ................................................................................ 3 - 76
System power-up sequence.......................................................................... 3 - 76
Inoperative printer problems........................................................................ 3 - 80
Main Board CPU operation ......................................................................... 3 - 80
Verifying print engine operation by printing a built in page. ...................... 3 - 81
Verifying power supply operation ............................................................... 3 - 81
Measuring power supply voltages ............................................................... 3 - 81
Inspecting the power supply fuses ............................................................... 3 - 82
Testing for shorted drivers ........................................................................... 3 - 83
Testing for a shorted motor.......................................................................... 3 - 84
Testing motor and solenoid resistances ....................................................... 3 - 84
Paper Path and Media-based Problems................................................................ 3 - 85
Media-based problems ................................................................................. 3 - 85
Paper-pick errors.......................................................................................... 3 - 85
Print transfer jams ........................................................................................ 3 - 86
Checking the process motor and drive train ................................................ 3 - 86
Media skews passing through the paper path .............................................. 3 - 87
Print Image Quality Problems.............................................................................. 3 - 88
Not printing.................................................................................................. 3 - 88
Missing ink or light colored ink band running length of print..................... 3 - 89
Color is uneven ............................................................................................ 3 - 90
Streaks or lines down the print .................................................................... 3 - 91
Scratches parallel to the long axis of printing, particularly with film ......... 3 - 92
Printing too light or too dark........................................................................ 3 - 93
White portion of print is colored.................................................................. 3 - 94
Fuzzy Text ................................................................................................... 3 - 95
Poor primary color fills................................................................................ 3 - 96
Ghosting....................................................................................................... 3 - 97
Poor small text resolution ............................................................................ 3 - 98
Vertical line appear wavy ............................................................................ 3 - 99
Oil streaks on print..................................................................................... 3 - 100
Incomplete image transfer to paper ........................................................... 3 - 101
Ink smears on first side of duplex print ..................................................... 3 - 102
Repeating print defects on print................................................................. 3 - 103
Wrinkling ................................................................................................... 3 - 104
Image is offset or cut off............................................................................ 3 - 105
Oil streaks on top of print .......................................................................... 3 - 105
Poor ink adhesion, poor image durability.................................................. 3 - 105
Evaluating the printhead and cap/wipe/purge system........................................ 3 - 106
Troubleshooting following cap/wipe/purge installation ............................ 3 - 112
Macintosh printing problems ............................................................................. 3 - 115
Image never prints ..................................................................................... 3 - 115
Image is rotated 90 degrees ....................................................................... 3 - 115
Image prints in black-and-white ................................................................ 3 - 115
Printer isn't in the Chooser ........................................................................ 3 - 116
Windows printing problems............................................................................... 3 - 117
ii Phaser 840/850/860/8200 Color Printer - Service Manual
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