Key Sense Trouble (Keypad) - LG KF700 Service Manual

4.4 Key sense trouble (KEYPAD)

Key Sense sequence of KF700 is :
Default condition ROW(0-3) is 2.7V ßú Press the key
→
Scan pulse( Col => Row )
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Only for training and service purposes
→
MSM sense what key pressed.
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4. TROUBLE SHOOTING
→
Corresponding ROW(x) and COL(x) go to 0V
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