- Printer Owner's Guide

Recording the Diagnostic Display Light Pattern
Understanding
the Diagnostic
Lights
During system startup, the diagnostic display lights flash on
and off in different patterns as the system startup tests are
performed. The light patterns are not random. They represent
the hexadecimal number of a test action or result, in binary
format–when a light is on, it represents a 1; off, it represents a
0.
For instance, when the startup tests are completed successfully
and your system is in console mode, the diagnostic display lights
display the hexadecimal number DD, the binary representatation
for which is displayed in Table 14–4.
When your system is in program mode, the diagnostic display
lights are either not lit or are set to display the hexadecimal
number 90, also shown in Table 14–4.
Table 14–4 Diagnostic Display Lights
Console Mode Display
76543210
Program Mode Display
76543210
When to
Record the
Diagnostic
Display Lights
If a problem is detected during system startup or when you run
diagnostic tests, you should record the diagnostic display light
pattern on the appropriate section of the Handling Problems
Worksheet at the end of this chapter. Notice that the diagnostic
display light numbers read 7 to 0, from left to right.
Be sure to note also when the display occurred, for instance,
during startup or after entering the show config command.
14–12 Running Diagnostic Tests