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Phaser 840/850/860/8200 Color Printer - Service Manual
Evaluating the printhead and cap/wipe/purge
system
A close relationship exists between the printhead and the cap/wipe/purge assembly. The
reliability and print quality of the printhead depends a great deal on the effectiveness of
the cap/wipe/purge assembly. If the cap/wipe/purge assembly is damaged, poorly adjusted
or if the vacuum system is not performing properly, the printhead will likely suffer lost,
unrecoverable jets. In some cases, the printhead can even be damaged by the
cap/wipe/purge assembly.
Before replacing a printhead, always verify that the cap/wipe/purge assembly is correctly
adjusted and performing properly.
1. Check printhead drive voltage (Head Adjust).
It is critical for new
printheads to run at the factory default of 128. Often, the printhead adjust is raised to
extend the life of older printheads. Adjusting it above 128 causes the jets to fail on
multi-page jobs and increases customer ink usage. DO NOT ADJUST THE
PRINTHEAD ON THE PHASER 850 OR 860, REPLACE THE PRINTHEAD.
2.
Service Test Print 2: Weak and Missing Jets
. Use this test print to evaluate the
cap/wipe/purge assembly and printhead performance.
■
If you see color mixing from one row to the next (for example, magenta jet 46 to
cyan jet 46), the cap/wipe/purge assembly blade may be damaged. Visually
inspect the wiper as described in Step 4 below.
■
If you see weak or missing jets, the problem may be caused by the
cap/wipe/purge assembly, vacuum system (tubing, air valve, or pump), or the
printhead. To isolate the problem, begin by checking the performance of the
cap/wipe/purge assembly and vacuum system as described in the following
steps.
■
If you see white “pin-stripes” spaced 0.1 inches (0.25 cm) apart across the page
(but not present on the test page), the problem is not with the cap/wipe/purge
assembly or printhead. Check for something binding the x-axis (such as a cable
rubbing the printhead).
Summary of Contents for Phaser 840
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