To Troubleshoot The Instrument; Primary Trouble Isolation - Agilent Technologies E4980A Service Manual

To Troubleshoot the Instrument

This section describes the basic procedural flow of troubleshooting when servicing the
E4980A. The primary procedural tool in this section is the flowchart. The flowchart
contains the entire troubleshooting path from a failure symptom to the isolation of faulty
assembly, and will direct you to the completion of repair in an ordinary manner through the
possible failure symptoms. Reference letters (Yes/No) on the flowcharts point to
procedural steps that briefly explain the troubleshooting method to be performed next.

Primary Trouble Isolation

The primary trouble isolation in Figure 4-1 is to help direct you to the correct section for
troubleshooting the E4980A.
Step 1. Turn the E4980A power on
With the E4980A plugged in and the power turned off, the front panel orange standby LED
should be on. When the front panel power switch is turned on, the orange LED should go
out and the yellow-green LED should come on. Also, the fan should start rotating. In case
of unexpected results, go to "Power On Sequence Troubleshooting" on page 29.
Step 2. Check the display
• The power on test is executed once automatically before the measurements start. If the
power on test fails, go to "Troubleshooting Using Service Function" on page 32.
• If one of the following error messages A1 EEPROM write error, CPU Bd EEPROM
write error, CPU Bd FLASH ROM write error, Fan failed, or Power failed is
displayed during the measurement process, go to "Power On Sequence
Troubleshooting" on page 29 (check booting process).
Step 3. Check the basic function
If the front-panel, LCD display, data storage, remote interface or another function (except
for measurement part) does not work correctly, go to "Function Specific Troubleshooting"
on page 40.
Step 4. Check the measurement function
If the E4980A fails any of the performance tests, go to "Performance test failure
troubleshooting" on page 57.
A faulty part should be replaced as outlined in Chapter 5 which gives replacement
procedures for each part. The procedures required after part replacement are given in
Chapter 6.
Chapter 4
Troubleshooting
To Troubleshoot the Instrument
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