Keysight Technologies N9030B, Service Manual

Page: 69 / 617

N9030B PXA Signal Analyzer Service Guide 69
Boot Up and Initialization Troubleshooting
Potential Problems During Boot Process
Verify LCD Backlight Functionality
There are two backlights within the LCD assembly, one across the top and one
across the bottom. If only one of the backlights has burnt out, the other will
still function. Considering this fact, as well as the fact that the expected life
span of the backlights is much longer than the LCD itself, it is not very likely
that the backlights themselves would cause a completely blank display.
To determine if a blank display problem is backlight related:
1. Remove the AC power cord and then remove the instrument cover. Refer
to Chapter 16, “Assembly Replacement Procedures”, on page 429 in this
manual.
2. Remove the Top Brace. Refer to Chapter 16, “Assembly Replacement
Procedures”, on page 429 in this manual.
3. Turn the instrument on and allow enough time for it to completely
boot-up.
4. Shine a bright light at the display and look closely for the expected
information (a large flashlight should work). Since most of the display
section of the screen has a black background you will need to look at
either the area next to the softkeys or the area across the top of the
screen, since these sections will have the largest areas of lighter
information in them.
5. Can the expected display information now be seen?
If yes:
The problem is backlight related. Proceed to step 6 .
If not:
The problem is not backlight related. Skip to “Verify Video Signal
Path Integrity” .