Evaluating The Printhead And Cap/Wipe/Purge System; Faceplate Showing Blade Wipe With No Drops, Smudges Or Streaks - Tektronix PHASER 840 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).
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.
2.
Print 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).
3. Visually check printhead faceplate.
faceplate to help evaluate whether the cap/wipe/purge assembly's
wiper blade and gasket are damaged.

Faceplate showing blade wipe with no drops, smudges or streaks

80 Phaser 840 and 850 Color Printers
It is critical for new
Closely examine the printhead's