LG KP175 - Page 52

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4. TROUBLE SHOOTING
LGE Internal Use Only Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
START
Check Battery Voltage
> 3.35V
Push power-on key
And check the level change
into low of PWRKEY
Check the voltage of
The LDO outputs at U10
2
Logic level at RPWRONN of U102
= HIGH(above 1.2V)
Is the phone power on?
The phone will
Properly operating
.
Charge or Change Battery
Check the contact of power key
Or dome-switc
h
Re-download software
VCORE=1.8V VVCXO=2.75V
VMEM=2.8V VSIM=1.8V or 2.85V
VEXT=2.8V VMIC=2.5V
Replace U102
Does it work properly?
Replace the main board
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
Replace U100 and Re-download software
CHECKING FLOW