Xerox Phaser 840 Service Manual page 95

The x-axis motor activates to move printhead off its locking post. The x-axis motor
9.
activates for three short bursts to ensure the printhead is in its far-left travel (printhead
home position). Then the x-axis motor is reversed to move the printhead to the center
the of the x-axis travel.
The process motor is again activated to tilt the printhead forward into the print
10.
position. The drum is rotated to sense it home position (The Phaser 850 printer uses a
slower rotation to find its home position).
A short cap/wipe/purge assembly motion is performed and the assembly is returned to
11.
its home position.
After the print engine is in a known, valid state, The AC heaters are enabled and the
12.
front panel display shows the warm-up progress. The Ready LED flashes; when
warm-up completes, the Ready LED lights solid.
The drum begins to rotate.
13.
If the temperature of the printhead ink reservoirs or jetstack are below the purge
14.
threshold, then the printer performs a head clean cycle.
When the ink in the printhead is molten and printhead temperatures are
a.
correct, the cap/wipe/purge assembly is positioned to the purge position.
The printhead tilts forward against the cap/wipe/purge assembly and a
b.
purge cycle begins.
The front panel indicates the printer is in a clean cycle.
c.
The temperature of the printhead, drum and paper preheater are allowed to stabilize at
15.
their operating temperatures and ink is melted if needed.
If needed, a cleaning page is printed at this time.
16.
A start page is printed (if enabled).
17.
The front panel displays a message that the printer is initializing and then ready.
18.
The print engine is initialized.
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