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Copyright © 200
9
LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
2. USB PART TROUBLESHOOTING
Turn on USB
YES
NO
YES
Connector check
(PN805, CN806, PN810 )
NO
Check power supply circuit (CN806)
Check micom interface circuit (PN805)
PIN13 : RX (IC805 PIN49 : TXD)
PIN14 : TX (IC805 PIN33 : RXD)
NO
NO
Check PN810 PIN2(D-), 3(D+)
Check OTI6888 (IC805)
Connector check (CN806)
OK
YES
“Checking” or
“USB” display check
NO
YES
Check PN810 1PIN : 5V
Reading OK check
NO
Check signal STCK, STREQ, STDATA
STCK : IC805 PIN52, IC801 PIN55
STREQ : IC805 PIN53, IC801 PIN54
STDATA : IC805 PIN54, IC801 PIN56
If PLAY, AUDIO
OUTPUT check
NO
NO