Appendix A Troubleshooting; Solving Common Problems - HP LD4220tm User Manual

A Troubleshooting

Solving common problems

The following table lists possible problems, the possible cause of each problem, and the
recommended solutions.
Problem
No image is
displayed.
Power is on,
power indicator
is blue, but the
screen appears
extremely dark.
Power indicator
is amber.
Out of Range
message
appears.
Check signal
cable message
appears.
Unknown
Product
message
appears when
the display is
connected.
Key Lock On
message
appears when
pressing the
Menu button.
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Appendix A Troubleshooting

Possible cause Solution
Power cord is Be sure the power cord is properly connected to the outlet.
not connected.
●
Verify that the outlet has power to it.
●
Check that the fuse or breaker has not tripped or burned out.
See if the power switch is turned on.
Might need service.
Screen needs Adjust brightness and contrast again.
adjustment.
Backlight might need repair.
Display is in Move the mouse or press any key on the keyboard.
power saving
Turn off equipment and then back on.
mode.
Input signal is The signal from the media player/computer (video card) is out of the vertical or
out of frequency horizontal frequency range of the display. Adjust the frequency range by referring to the
range. specifications in this manual (maximum resolution: RGB—1920 x 1080 @ 60 Hz; HDMI
—1920 x 1080 @ 60 Hz; DisplayPort—1920 x 1080 @ 60 Hz).
NOTE: Vertical Frequency—To enable the user to watch the display, the screen
image should change multiple times every second like a fluorescent lamp. The vertical
frequency or refresh rate is the number of times the image displays per second. The
unit is measured in Hz.
Horizontal Frequency—The horizontal interval is the time to display one vertical line.
When 1 is divided by the horizontal interval, the number of horizontal lines displayed
every second can be tabulated as the horizontal frequency. The unit is measured in
kHz.
Signal cable is The signal cable between the media player/computer and display is not connected.
not connected.
Make sure that the signal cable is properly connected.
Press the INPUT button on the remote control to check the input signal.
Display driver is Install the display driver, which is provided with the display or download from the HP
not installed. website www.hp.com.
See if the Plug and Play function is supported by referring to the video card user
manual.
Key Lock The control locking function prevents unintentional OSD setting changes. To unlock the
controls, simultaneously press the Menu button and right arrow ► button for several
function is
turned on. seconds. (You cannot set this function using the remote control buttons. You can set
this function with the display only.)
ENWW