HP L1506 Service Manual page 35

15" LCD Color Monitor
9.2.3 Key Board
OSD is unstable or not working
Is Key Pad Board connecting normally?
Is Button Switch normally?
Is Key Pad Board Normally?
OK
OK
OK
Check Main Board
NG
Connect Key Pad Board
NG
Replace Button Switch
NG
Replace Key Pad Board
35
HP L1506