Read LG 47SL90QD-SA (CHASSIS:LJ91L) Service Manual online
14. USB Trouble Shooting
• Exception
- USB power could be disabled by inrushing current
- In this case, remove the device and try to reboot the TV (AC power off/on)
Check USB 2.0 Cable
Y
Check P704
N
Y
Y
Check USB device
If devuce is 2.5 inch HDD,
Check power adaptor
Replace Jack
Check 5V voltage level at L703
N
Y
Maybe BCM3556(IC100)
has problems. Replace It.
Replace one of
IC701/L703/IC806/Q810/L819
& Recheck
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