Xerox Phaser 8860, Service Manual

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09/2007
6-25 Phaser 8860/8860MFP Service Manual
Print Engine Check Menu Tests
Diagnostics Initial Issue
Drum Maintenance Drive Test
This test determines if the drum maintenance mechanism is operating by placing the Drum
Maintenance Kit against the Drum for a short time. First with the roller and blade in contact with
the Drum, then just the blade. This test requires that the Drum is clean and not dry to provide a
predictable interface surface.
NOTE: If this test indicates the Drum Maintenance Kit is not functioning, the Tilt Axis Drive test
may also produce out of range results due to the effect of the Drum Maintenance Kit on that
test.
Tilt Axis Drive Test
This test exercises the head tilt mechanism. This includes the Drum Maintenance Kit, Process
Drive, Media Drive Assembly, Wiper Assembly, and Head Tilt Solenoid and Gear.
·If the Tilt mechanism does not engage, the test will abort with one of the following messages:
• Printhead unlatch time-out - The Drum Maintenance following error did not exceed 105%
of the Drum Maintenance only max with in the Process Motor tilt drive interval.
• The wiper stalled during the scan before unlatching the Head Tilt Gear. The most likely
cause is the Wiper Blade is not level causing the high end to contact the drip bib and stall-
ing the wiper axis before unlatching the gear. Other causes could be that the Head Tilt
Gear is jammed (full of ink), or not properly biased (Head Tilt Spring missing or defective).
Also the trip lever could require extra effort to lift (flat spring stronger than usual, rough or
warped engage surface with gear, binding/drag from Head Tilt Solenoid), causing the
wiper axis to stall before contacting the drip bib. Extra drag in the wiper mechanism could
also cause a stall.
• Process Drive stalled before the Head Tilt Gear was unlatched.
Drive problems on either axis could cause the respective motor to stall and the test to abort.
The Wiper Drive and Drum Maintenance Drive tests would test the basic drive mechanisms. If
the Head Tilt Gear fails to engage the tilt mechanism, the test aborts, and all R values are
undefined. If peak values are high, there could be an issue with a weak Process Drive, friction
in the tilt cam drive train, the cam surfaces (lubrication), the Head Tilt Spring, or something
impeding the Printhead from tilting (warped insulation on the side, X-Axis misalignment, or the
Printhead being compressed against the Electronics Module. If the peak values are low, check
the Head Tilt Spring.
Wiper Drive Test
This test exercises the Wiper Assembly, Printhead latching mechanism, Head Maintenance
Clutch, and related parts. This test assumes that the tilt drive and the Wiper Assembly mecha-
nisms are functioning correctly. Run the Tilt Drive test first to verify correct operation of that
mechanism. This test activates the tilt mechanism to move the Printhead out of the way. Next,
the Media Drive Assembly drives the Wiper Blade over it's range of motion.
1 Loaded Average Y-axis fol-
lowing error (mpts) N/A Reports the average Y-axis following
error during the Roll With Transfix Roller
Down interval.
2 Loaded Y-axis following error
ripple (mpts) N/A Reports the difference between the max
and the min Y-axis following error during
the Roll With Transfix Roller Down inter-
val.
3 Time to last contact (sec) N/A Reports the time from the unload com-
mand to the engine until the drum indi-
cates no further contact.
Table 28 Drum Maintenance Drive Nominal Values
R# Characteristic Typical Value Result
0 Time to blade first contact
(sec) N/A Reports the time to blade contact with
the Drum.
1 Time to roller first contact
(sec) N/A Reports the time to roller contact with the
Drum.
2 Roller/Blade loaded average
Y-axis following error (mpts) N/A Reports the average Y-axis following
error during the Roll With Both Loaded
interval.
3 Roller/Blade loaded Y-axis
following error ripple (mpts) N/A Reports the difference between the max
and the min Y-axis following error during
the Roll With Both Loaded interval.
4 Roller Disengaged Time
(sec) N/A Reports the time till the drum indicates
no further roller contact.
5 Blade loaded average Y-axis
following error (mpts) N/A Reports the average Y-axis following
error during the Roll With Blade Loaded
interval.
6 Blade loaded Y-axis follow-
ing error ripple (mpts) N/A Reports the difference between the max
and the min Y-axis following error during
the Roll With Blade Loaded interval.
7 Blade Disengaged Time
(sec) N/A Reports the time till the drum indicates
no further blade contact.
Table 27 Transfix Drive Nominal Values
R# Characteristic Typical Value Result
Table 29 Tilt Axis Drive Nominal Values
R# Characteristic Typical Value Result
0 Tilt Engage Wiper Position
(min) N/A Reports the distance from the wiper
Home position to the tilt cam engage
point.
1 Pre Standby peak Location
(deg) N/A Reports the distance around the tilt cam
from the tilt engage position to the pre
standby peak.
2 Pre Standby peak Av
(counts) N/A Reports the Process Drive following
error at the pre standby peak location.
3 Post Wipe Peak Location
(degrees) N/A Reports the distance around the tilt cam
from the tilt engage position to the post
wipe peak.
4 Post Wipe peak Av (counts) N/A Reports the pm motor following error at
the post wipe peak location