Sony BVM-F250 Operation Manual page 128

Symptom
The function of the function button
of the controller is different from
that of the panel display.
The zebra pattern does not go off. An Over Range error is detected.
The picture is not displayed on the
monitor when you have connected
two or more computers via the
DisplayPort connector through a
switch box or other device and
switch the input signal from one
computer to another.
128
Troubleshooting
Assumed causes
Another function has been assigned to
the button.
The zebra pattern is set to be
displayed in the Over Range portion,
and the detected Over Range
information is retained.
You have switched from a computer
that is in power save mode to another.
Remedy
See the Function Key menu (page 84) of the
Controller menu to confirm the function assigned to
the function button.
Set Over Range (page 76) to Off in the On Screen
Set menu of the System Configuration menu.
Note
If the OVER RANGE lamp lights, adjust the contrast
or brightness to a lower level.
Do not switch from a computer in power save mode
to another.
If the picture is not displayed after switching, turn
the monitor off then back on again or switch back to
the computer in power save mode and bring in out
of power save mode.