Keysight Technologies TrueIR U5855A Service Manual page 39

Table 3-1 Troubleshooting hints (continued)
Malfunction
The LCD displays a white screen.
The LCD screen indicates
abnormality in the image
gradation.
No images displayed on an
external monitor during video out.
The date/time setting is reset to
default.
The battery operating time is
shorter than 4 hours (out of
specification).
Battery charging error is
indicated.
Unable to update the firmware.
If you encounter any problem not covered in the above table, contact your nearest Keysight
N O T E
Service Center.
U5855A Service Guide
Probable cause
Power is not turned on.
A connection failure occurs between the
flexible cable (FPC) of the LCD and the
main board, or the FPC is disconnected.
A connection failure occurs between the
flexible cable (FPC) of the LCD and the
main board, or the FPC is disconnected.
The wrong video out format is set.
The coin battery is weak, or the coin
battery drops out of the battery
compartment.
The battery life is depleting.
The surface of the battery terminals is
dirty.
The battery fails to operate properly.
The firmware update operation is
performed incorrectly.
The wrong folder name is used.
Troubleshooting and Repair
Operating and Troubleshooting Hints
Troubleshooting procedure
Check the LED status indication of the
power on/off key.
Connect the U5855A to an external
monitor and check the display. If still fails,
return the U5855A to Keysight for
servicing.
Connect the U5855A to an external
monitor and check the image gradation. If
still fails, return the U5855A to Keysight
for servicing.
Set the correct video out format for both
the U5855A and the external monitor.
Set the date/time and restart the U5855A.
Check if the date/time setting is correct. If
not, return the U5855A to Keysight for
servicing.
Replace with a new battery.
Check the battery terminals and clean the
surface properly.
Check if the battery is installed correctly,
and re-install if necessary.
Check the proper procedure for firmware
update and try again. If still fails, return
the U5855A to Keysight for servicing.
Check if the folder format is correct and try
again. If still fails, return the U5855A to
Keysight for servicing.
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