Printronix P9012, Maintenance Manual

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4–14 Troubleshooting
Diagnostic Self–Tests
Run diagnostic self–tests to check the print quality and operation of the
printer. The self–tests are listed below.
NOTE: Included with the description of each diagnostic test is a list of items
that may require field replacement or adjustment if the test produces
a bad print pattern.
•
Shift Recycle
A “sliding” alphanumeric pattern useful for identifying missing or
malformed characters, improper vertical alignment, or vertical
compression.
Shuttle assembly
Hammer bank cover
Hammer spring
•
All E’s
A pattern of all uppercase letter E’s useful for identifying missing
characters, misplaced dots, smeared characters, improper phasing, or
light/dark character variations.
Ribbon
Hammer bank cover
MPU Sensor
Hammer spring
Hammer coil
•
E’s plus TOF
A pattern of all E’s followed by a form feed to the next page top of
form, useful for identifying paper motion or feeding problems (e.g.,
paper path obstruction, improper forms).
Hammer bank cover
Power supply PCBA
Mechanism driver or MCU PCBA
Paper motion sensor or cable
Paper feed motor or belt
Splined shaft bearings
Tractors or tractor belts