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Phaser 840 and 850 Color Printers
Drum position sensor assembly (Phaser 840 printer)
1.
Remove the left and right cover.
2.
Remove the top cover.
Caution
Unhook the head-tilt spring to avoid possible damage to the
printhead and drum.
3.
Disconnect the drum home-position sensor wiring harness from J180 of
left I/O board leading to the drum position assembly. Disconnect the
drum position encoder sensor at the drum position assembly.
4.
Remove the clear plastic dust cover from the drum position assembly.
5.
Precisely mark the end of the drum shaft relative to the drum home flag
on the drum position sensor assembly; this is not necessary if you are
also replacing the drum (as part of the drum/transfix assembly).
6.
Rotate the X-axis drive gear to move the printhead to its print position.
7.
Rotate the tilt gear to orient the gear’s missing teeth to the drum
position sensor assembly’s rear mounting screw.
8.
With a small, flatblade screwdriver, slide the retaining spring out of the
encoder wheel’s groove toward the encoder disk.
Marking the drum home flag sensor alignment
840-4-17
Mark on the drum shaft to
align with the home flag
Drum home
flag
Drum position
encoder wheel
Summary of Contents for Phaser 840
Page 11: ...xii Phaser 840 and 850 Color Printers ...
Page 65: ...54 Phaser 840 and 850 Color Printers ...
Page 101: ...90 Phaser 840 and 850 Color Printers ...
Page 125: ...114 Phaser 840 and 850 Color Printers ...
Page 134: ...Service Guide 123 Clearing PostScript NVRAM menu item ...
Page 135: ...124 Phaser 840 and 850 Color Printers ...
Page 166: ...Service Guide 155 Figure 1 Cabinet FRUs 7 5 6 8 1 2 4 0388 21 3 9 9 ...
Page 170: ...Service Guide 159 Figure 3 Paper path FRUs 0388 80 2 1 5 11 10 9 12 6 4 3 7 13 8 11a 11b ...
Page 172: ...Service Guide 161 Figure 4 Motor and fan FRUs 0388 14 7 4 3 5 6 2 1 ...
Page 174: ...Service Guide 163 Figure 5 Circuit board FRUs 4 3 5 2 1 9 7 6 8 10 11 13 0388 81 12 7a ...
Page 176: ...Service Guide 165 Figure 6 Solenoid and clutch FRUs 4 5 3 2 1 0388 23 ...
Page 182: ...Service Guide 171 Figure 9 High capacity PaperTray 0388 65a 1 2 ...