LG SPH4B-W - Page 46

3-17
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ELECTRICAL TROUBLESHOOTING GUIDE
USB_5V is not 5 V
Check F301 Voltage 25 VA
Check FB305 Voltage 5.1 VA
Check Adapter
Replace Main PCB
YES
YES
YES
NO
NO
Check FB304 Voltage 12 VA
Check FB306 Voltage 5 V
Replace Main PCB
Replace Main PCB
YES
YES
NO
NO
OK
ADAPTER POWER CIRCUIT