Usb Trouble - LG GD88O Service Manual

4. TROUBLE SHOOTING

4.12 USB trouble

USB Initial sequence of GD880 is :
USB connected to GD880
VERG_MSME_1.8V is about 1.8V
Start
Cable is insert?
VCHG_VBUS is about
to 5V?
TP4 CLK is OK?
TP5,TP6 signal is out?
Change the Main board
130 P
LGE Internal Use Only
VCHG_VBUS(FL400) go to 5V
USB_CLK is OK(R210)->USB work
NO
YES
NO
YES
NO
YES
NO
YES
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4. Trouble Shooting (BB)
Cable insert
Check TP2
Check TP3
Check TP1
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