Printronix T5000 Software Manual page 271

It is possible that more than one failure message can be reported in a bar
code report. However, the printer can display only one error message at a
time. Thus, when multiple failures are detected, only one message displays
and the rest are ignored, based on the following failure priority hierarchy.
Priority Failure Message
1 Encodation
(highest)
2 Checksum
3 Quiet Zone
4 (Symbol) Contrast
5 Percent Decode
6 Defects
7 Decodeability
8 PDF 417 Gap
9 Calibration
10 Overall Grade Failure
11 Internal Data Format
Error
12 Modulation
13 Minimum Reflectance
14 Minimum Edge
(lowest) Contrast
Viewing Telemetry Data
Operator Panel
Message
Bar code improper
data format
Checksum Failure
Bar code quiet
zone too small
Contrast too low
Check media
Poor scanning
Check media
Poor scanning
Inspect head
Unscannable code
Check media
Poor scanning
Check media
Calibration
Warning
Overall Grade
Failure
Error
Data invalid
Modulation Fail
Check head&heat
RMin Fail
Check head&heat
Edge Ctst Fail
Check head&heat
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