LG GX300 Service Manual page 85

4. TROUBLE SHOOTING
CHECKING FLOW
START
Check Battery Voltage
> 3.2V
Push power-on key
And check the level change
into high of POWERKEY(TP1)
Check the voltage of
The LDO outputs at U102
Logic level at RPWRON of R227
= HIGH ?
Is the phone power on?
The phone will
Properly operating.
LGE Internal Use Only
NO
YES
NO
YES
NO
VCORE(TP4)=1.2V, VPMU(TP11)=1.2V. VRTC=2.3V,
VDD_1.8V(TP5)=1.8V
VAUX(TP7)=2.8V, VMMC(TP13)=2.8V, VDD_RF2(TP10)=2.5V,
VRF1(TP6)=1.8V, VDDTRX(TP8)=1.3V, VDDMS(TP2)=1.3V,
YES
VDDXO(TP3)=1.3V, VDDTDC(TP9)=1.3V
NO
YES
NO
YES
86/158
4. TROUBLE SHOOTING
Charge or Change Battery
Check the contact of power key
Or dome-switch
Replace U102
Re-download software
Replace U102 and Re-download software
Does it work properly?
NO
Replace the main board
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