Agilent Technologies 8935 Series, Руководство пользователя

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56 Chapter 3
Troubleshooting
Self-Test Diagnostics (Step 1)
Reading LED Codes
When the self-test diagnostic reports a failure, more information about
the failure may be available inside the Test Set. This additional
information is output to the four LEDs on the top of the A2A31
Controller assembly. The failure codes are sent out as code sequences.
Figure 3-7 on page 58 and the tables following it document some of the
more useful code sequences. You may need to run the Self-Test
Diagnostic several times to decode a particular LED sequence.
NOTE
The LEDs output self-test diagnostic codes only when the Test Set is
powering up. The LEDs remain off when the self-test diagnostic is
initiated through programming or when running the functional
diagnostics. To read the LED codes, the Test Set’s cover must be
removed.
If the Test Set has no faults that can be detected by the Self-Test
Diagnostic, the four LEDs on the Controller assembly will light and
remain on for about ten seconds. During that period, a short beep will
be heard. Then the LEDs will extinguish and remain off.
If a fault is detected during the test:
1. The four LEDs will go on for about four seconds.
2. The LEDs will blink a failure code which corresponds to the error
listed in Table 3-1 on page 55 . Figure 3-8, "First LED Patterns," on
page 59 shows the blinking LED codes.
3. Two non-blinking LED codes will follow. The interpretation of these
codes depends on the preceding blinking code. Two sets of the
non-blinking codes are listed: see
Figure 3-9 on page 60 and Figure
3-10 on page 61 .
4. If there is more than one failure, the test will loop back to step 2 and
repeat until the last failure is reported.