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4.4 Key sense trouble ( KEYPAD )
Key Sense sequence of KF310 is :
Default condition ROW(0-3) is 2.7V
→
Press the key
→
Corresponding ROW(x) and COL(x) go to 0V
→
Scan pulse( Col => Row )
→
MSM sense what key pressed.
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Only for training and service purposes
start
Check RA 400 0, R401 4
Row(0~ 4) is 2. 7V
Change Main Board
Change the Dome Sheet
Work well ?
Check short the Short ,
Row 0~ 4, COL 0~ 4
Some Point is short ?
Short Point clear
Change Main Board
YES
YES
NO
NO
NO
Change Main Board
YES
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Summary of Contents for KF310
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