Key Troubleshooting - LG E900 Service Manual

4.17 Key Troubleshooting

Key FPCB
Key FPCB consists of Volume Key & Camera Key & Front Key.
Start
Key press
( TP1 ~ 6 )
KEY_COL[0~3] is Low?
KEY_ROW[0~1] are High?
No
Change the Main board
And Retest
TP6
TP5
TP4
TP3
TP2
TP1
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Only for training and service purposes
Yes
Change the KEY FPCB
Test
Net name
point
TP1 KEY_COL0
TP2 KEY_COL1
TP3 KEY_COL2
TP4 KEY_COL3
TP5 KEY_ROW0
TP6 KEY_ROW1
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4. TROUBLE SHOOTING
Voltage level
0V
0V
0V
0V
2.6V
2.6V
LGE Internal Use Only