Keyboard Faults 4 - Nokia NPL-4 Series Troubleshooting Instructions

NPL-4/5/RM-104
Troubleshooting Instructions

Keyboard faults 4

Keyboard
faults
4
Is PTT key working ?
Yes
Keyboard
faults
5
Copyright © 2005 Nokia Corporation. All rights reserved.
Page 78
Company confidential
Measure ROW4
line from S303.
No
Is it ~1.8v ?
No
Measure COL0 from
S300 when key is pressed.
Is there 50us pulse ?
Yes
Nokia Customer Care
Yes
Check S303, S300,
S301 and lines. If OK
change Z300.
If still fail change UPP
Check S300 and COL0
lines. If OK change
No
Z300.
If still fail change UPP
Change UPP
Issue 2 05/05