3-23
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Only for training and service purposes.
ELECTRICAL TROUBLESHOOTING GUIDE
KEY PART
Replace the Cable1
Check R520 Pull-up Resistor
YES
Check CN505 1, 2 pin
Voltage 3.3 V
Check the connecting cables
Check RA01, RA04, RA05, RA06
Replace the Key PCB
YES
NO
Check SWA01, SWA02,
SWA03, SWA04
OK
YES
YES
NO
NO
OK
2. KEY PART