HP 8924E, Assembly

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Chapter 2, Troubleshooting
More About Step 1- Run the Power-Up Diagnostic
N:\mkt\MANUALS\HP8924C\ALR\trouble.fb
More About Step 1- Run the Power-Up Diagnostic
If the Test Set powers up with the message:
”All self tests passed.”
it is still possible to have the following digital
problems:
• Intermittent failure in any digital assembly.
• Input or output failure on any I/O port of the A14 Host Serial I/O assembly.
• Key failure (other than stuck keys) on the A1 Keyboard.
If all Self-Test Diagnostics pass, and the front-panel keys and knob work, you can
assume that the digital control assemblies work.
If the Test Set powers up with the message:
”One or more self-tests failed. Error code:<hexadecimal
error code>”
:
See "Description Of Self-Test Diagnostic," in chapter 14, on page
541
for further details on troubleshooting with the Self-Test Diagnostic.
If the Test Set fails to power-up at all:
• If there is no image on the display, see figure 8, "Troubleshooting a Blank Display,"
on page 80 .
• If an error message appears and remains in the center of the display, or if the Test Set
does not respond to any keys or HP-IB commands, the Test Set may be configured to
power-up to a custom procedure (rather than the default screen) and that procedure may
have errors. This feature is initiated by setting
Autostart
to
On
from the TESTS
(Execution Conditions) screen. To correct this fault, turn the power off, then the power
on while holding down the MEAS RESET and Hz keys until an image appears on the
screen. Note: this will erase all existing programs and Save/Recall settings.
• If the Test Set does not power-up properly, but the fan operates and the power supply
voltages are correct on the Filter regulator (A20) outputs, the Host Controller (A16)
may be failing. It may be possible to run the Self-Test Diagnostic and read the test
results using the diagnostic LEDs on the Host Controller assembly.
See "Description
Of Self-Test Diagnostic," in chapter 14, on page 541 for details.