Optima L903AD+ Service Manual page 44

19" LCD Color Monitor Optima L903AD+
8.2.3 Keypad Board
OSD is unstable or not working
N
Connect Key Pad Board
Is Key Pad Board connecting normally?
Y
N
Replace Button Switch
Is Button Switch normally?
Y
N
Replace Key Pad Board
Is Key Pad Board normally?
Y
Check Main Board
44