LG LG-D618 - USB Trouble Shooting

3. TROUBLE SHOOTING
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Only for training and service purposes
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3.18 USB Trouble Shooting
The sequence of LGD618 USB is,
USB connected to LGD618 -> VBUS_USB_IN(C816) goes to 5V -> USB_D+ go to 3.3V -> USB_DATA is triggered -> USB
work
USB Trouble shooting is shown below.
Battery voltage higher than 3.2V?
Change or charging the Battery
Yes
Yes
Yes
Yes
Yes
Change the Main PCB
Start
VBUS_USB_IN voltage(4.7V~5V) TP1:
R10000
Change TA or uUSB cable
Insert USB Cable
No
No
No
No
No
Check +5V0_VREG_BHARGER is high?
TP2 : C4142
Check U4100(PM8226)
Check U4100(PM8226)
Check Lower FPCB
Check VREG_L10_1V8 (TP3:C2359) and
VREG_20_3V075
(TP4:C2360) is high?
USB_D_P is high?
(TP5:FL101)