Keysight Infiniium MSOS404A - Display Troubleshooting

Troubleshooting 4
S-Series Oscilloscopes Service Guide 65
Display Troubleshooting
NOTE
When you connect an external monitor the first time, it may display the start-up BIOS
information and then go blank when Windows starts up. If so, use the Windows settings to
enable the external monitor.
Connect external
monitor to VGA
port. Turn on power.
Does display
appear on ext.
monitor?
Is front panel
display
scrambled?
Is front panel
display black?
Check LED backlight cable,
front panel power cable, and
backlight enable connector
Still black?
Replace keyboard
assembly rear board
Still black?
Replace LCD Still black?
Done. Go to
“Primary Trouble
Isolation”
No
Yes
No
Yes
Yes
Replace
motherboard
Replace
motherboard
Yes
No
Yes
Check display cable
connection to
monitor
Yes
Still scrambled?
Replace
motherboard
Yes
No
No