A3 Display Test; Checking The A2 Usb Board - Keysight Technologies N5221A Service Manual

Troubleshooting
Front Panel Troubleshooting

A3 Display Test

The display should be bright with all annotations and text readable. The display
test allows you to check for non-functioning pixels and other problems.
If the display is dim or dark, refer to
Problems" on page
What Is a Damaged Pixel?
A pixel is a picture element that combines to create the image on the display. A
pixel is about the size of a small pin point.
A damaged pixel is pixel that has a constant blue, green, red, or black
appearance that will not change.
How to Run the Display Test
To run the display test, perform the following:
Press UTILITY
A multi-color screen is displayed. Be prepared to look for the symptoms
described in
screen.
How to Identify a Faulty Display
A display is considered faulty if:
— More than 0.002% of the total pixels have a constant blue, green, red, or
black appearance that will not change.
— Three or more consecutive pixels have a constant blue, green, red, or black
appearance that will not change.
If the A3 display assembly is determined to be faulty, replace it. Refer to
"Removing the A3 Display Assembly and the Touchscreen" on page

Checking the A2 USB Board

To verify proper operation of the USB board:
— Connect a known good USB device, such as a USB mouse, to a front panel
USB port.
— Wait 15 seconds for the analyzer to verify the device connection, and then
check the operation of the USB device.
— If the device performs correctly, the USB board is functioning properly.
— If the device does not perform correctly, the USB board is faulty. Refer to
"Removing the A2 USB Board" on page
Keysight N5221A/22A Service Guide
4-14.
, then
System Service
"How to Identify a Faulty Display."
"Troubleshooting LCD Display
, then , then
Display Test
More
Follow the instructions on the
7-10.
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7-12.
4-19