Samsung SCH-811 Service Manual page 33

6-1-4 Abnormal Key Data input
Check initial status
Scanning signals
output from U101, C5, B4, D5, A5
Check U101 A2, A3, C4, B5, E5
Normal key data input?
SAMSUNG Proprietary-Contents may change without notice
C6, A5, D6
Yes
Yes
Check J103
Yes
Yes
END
Check U101
No
No
Replace the key pad assembly
6-4