Agilent Technologies E4440A, Service Manual

Page: 46 / 436

46 Chapter 2
Overall Troubleshooting
Troubleshooting Power-up Problems
Troubleshooting Power-up Problems
CAUTION
If the instrument shows any of the following symptoms, immediately
unplug the instrument from the ac power line:
• Smoke or unusual noise from inside the unit.
• A circuit breaker or fuse on the main ac power line opens.
These potentially serious faults must be corrected before proceeding.
Refer to
“Troubleshooting Power-up Problems” on page 46 .
NOTE
Power-up problems include an instrument failing to boot, an instrument
that completes the boot process but displays error messages, or an
instrument that appears to be inoperative (dead)
.
When powered up the instrument performs a boot process and CPU
self-diagnostics, followed by a routine of internal auto-alignments.
These tests evaluate the instrument operation; if a problem is detected
an error message will be displayed, or the rear panel LEDs will indicate
a problem.
Table 2-1 Initial Symptoms
Symptom Troubleshooting Section
No front or rear panel LEDs "Troubleshooting Power-up Problems" on page 46
Blank display screen "Troubleshooting Power-up Problems" on page 46
Fans not operating "Troubleshooting Power-up Problems" on page 46
Instrument did not boot "Troubleshooting Power-up Problems" on page 46
Power-on auto-align tests failed "Troubleshooting Using Auto-Align Tests" on page 49
No response when keypad is pressed "Troubleshooting Power-up Problems" on page 46
Error Messages “Instrument Messages and Functional Tests” guide
Low signal level “RF Assembly Quick Check - E4440A, E4443A,
E4445A” on page 75
For E4446A and E4448A see page 95