LG XA64 - Usb Part

13. USB PART
YES
NO
NO
YES
YES
YES
Turn on USB
Check CN401
Check CN401 pin2 5V
Check U502 pin55, 57
Check power supply circuit USB +5V
Check CN401 pin3, 4 (D+, D-)
Check U503 pin3, 4
Check uCOM IC603
pin116, 117 (D+, D-)
Check uCOM IC603
pin116, 117 (D+, D-)
NO
NO
NO
NO
NO
NO
Check "CHECKING"
or "USB" display
Check reading OK
If play, check audio output
OK
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ELECTRICAL TROUBLESHOOTING GUIDE