LG SN4A - Page 48

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ELECTRICAL TROUBLESHOOTING GUIDE
No VCC_5V,
USB_5V
Check F301 Voltage 25 VA
Check FB305 Voltage 5.1 VA
Check Adapter
Replace IC305
YES
YES
YES
NO
NO
Check R371 Voltage 12 VA
Check R378 Voltage 5 V
Replace IC302
Replace IC306
YES
YES
NO
NO
OK
ADAPTER POWER CIRCUIT