Xerox Phaser 840, Service Manual, Page: 101 / 287

Troubleshooting 3 - 85
Paper Path and Media-based Problems
Media-based problems
1.
Check that the correct type of media is being used, for information on the correct media
type and sizes refer to the
Paper Tips page, which is printable from the printer Front
Panel Menu. See also SB403 & SB409.
2.
Inspect the paper for bent, torn or folded corners. Check for stuck sensor flags.
3.
Check to ensure no small pieces of paper are in the paper path.
4.
Ensure that the correct media is in the correct media tray. The tray switch actuators
indicate the size and the type of media loaded in the tray; the printer does not directly
sense the size or type of media.
5.
Ensure the correct weight of paper is being used. Refer "Specifications" on page 1-31
or the built-in embedded page, “Paper Tips”.
6.
Ensure that envelopes are of the acceptable size and orientation with the side-flap up.
Paper-pick errors
Paper-pick errors occur when the media in the media tray mispicks or the printer
double-picks two or more sheets of paper.
1.
Inspect the paper path for obstructions.
2.
Ensure that the media fits properly in the tray. With the left edge of the stack of paper
flush against the tray rail, there should be a small gap between the opposite edge of the
stack of paper and the opposite side rail. The Phaser 860 has tabs on the back-stop to
prevent over filling the tray.
3.
In humid environments, keep media sealed in packaging until it is needed for printing.
Flip over the media in the tray.
4.
When installing paper, push down the stack of paper until the tray's lift-plate locks to
the bottom of the tray. This prevents the top sheet of paper from being mis-positioned
as the tray is inserted in the printer.
5.
Ensure the High-Capacity Paper Tray (lower tray) assembly pick roller is installed
correctly. (It can inadvertently be installed backwards.)
6.
Clean the pick roller using the cleaning procedures "Pick Roller Cleaning Method" on
page 6-175
Paper dust can coat the pick roller and affect its ability to grip the paper and
pull it out of the tray. Also clean the transport rollers if they are visibly dirty. See
SB402.
7.
Check that the pick roller is being rotated. Diagnostics can be used to verify.
8.
Use diagnostic’s to run “Verify Drive Current Requirement Test” ( Phaser 840/850) or
“Paper Path Drive” test (Phaser 860), to check the operation of the paper-pick system.
9.
Inspect the wiring harness leading to the paper-transport clutch for nicks, cuts or
crimped wiring. Ensure the connector is seated.
10.
Inspect the rollers, bushings and gears of the paper path.