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NPL-4/5/RM-104
Company confidential
Troubleshooting Instructions
Nokia Customer Care
Page 76
Copyright
© 2005
Nokia Corporation. All rights reserved.
Issue 2 05/05
Keyboard faults 2
Keyboard
faults
2
Is UI-module
keymatrix working ?
Try to change
UI -module. Is it
working now ?
Measure SLEEPX signal
from J403 when key
pressed.
Is it ~1.8V ?
When keypad is
pressed, the LED's are
turned on ?
Faulty UI-module.
Retest
Check ROW0-4 lines,
X301. If OK change
Z300. If still fails change
UPP.
Check ROW0-4 lines,
X301. If OK change
Z300. If still fails change
UPP.
Check ROW0-4 lines,
X301. If OK change
Z300. If still fails change
UPP.
Measure ROW0-4
lines from X301.Are
they HIGH ?
No
Yes
No
No
Yes
No
Yes
No
Keyboard
faults
3
Yes
Display
faults
Yes