Only For Training And Service Purposes - LG MG295 Service Manual

4. TROUBLE SHOOTING
Checking Flow
Check Battery Voltage
And check the level change
into low of POWERKEY
The LDO outputs at U103
Logic level at RPWRON of U103
LGE Internal Use Only
START
> 3.35V
YES
Push power-on key
YES
Check the voltage of
1V8_VCORE=1.8V
2V8_VMEM=2.8V
2V8_VEXT=2.8V
YES
2V5_VMIC=2.5V
= HIGH(above 1.2V)
YES
Is the phone power on?
YES
The phone will
Properly operating.
NO
Charge or Change Battery
NO
Check the contact of power key
Or dome-switch
NO
Re-download software
VVCXO=2.75V
2V 85_VSIM= 2.85V
1V8_VRTC=1.8V
NO
Replace U103
NO
Replace U100 and Re-download software
Does it work properly?
Replace the main board
Copyright © 2007 LG Electronics. Inc. All right reserved.
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NO

Only for training and service purposes