Samsung DSB-S300G Service Manual page 28

No USB memory Detected
at ´ DM(pin3), DP(pin4),
J1302(USB connector) on Front
Samsung Electronics
Check the ΠSignal at
pin 1, 3 of U502
Yes
Check the Voltage(5V) at
pin 5 of U502
Yes
Check Signal and Voltage
VBUS(pin2) of J1301
(Front Board)
Yes
Check Open or Short at
Board
Check Failure mode
No
of U302(STi5100)
Check Failure mode of
No
U501 and Circuit
Check Short or Open at
No
J1202 and Flat cale Connection
Troubleshooting
ΠSignal at pin 1, 3 of U502
´ DM(pin3), DP(pin4),
VBUS(pin2) of J1301
(Front Board)
5-9