Usb Error Correction Flow Chart - LG MAX220UB Service Manual

5. USB ERROR CORRECTION FLOW CHART

Something wrong with the USB?
Only "NO USB" or "USB CHECK" Display?
YES
Checked the USB VDD?
YES
Checked the USB
interface IC GND?
YES
Checked the USB
interface IC reset?
YES
Checked the USB
interface IC X-tal?
YES
Checked the
D+/D- Port?
YES
Checked the USB
indication Port?
YES
OK
5A 5B
NO
NO
IC501(4, 5, 7, 9, 12, 44, 49, 51, 74, 77, 81,
NO
NO
NO
NO
2-9
IC805, IC401(52)
102, 104, 116, 117)
IC401(42), R425
X502
IC501(52, 53)
IC501(52, 53)