Power On Trouble - LG GM210 Service Manual

4. TROUBLE SHOOTING

4.4 Power On Trouble

CHECKING FLOW
Check Battery Voltage
Push power-on key
And check the level change
into low of POWERKEY
Check the voltage of
The LDO outputs at U102
Logic level at RPWRON(DBBON) of D101
=
Is the phone power on?
Properly operating.
LGE Internal Use Only
LGE Internal Use Only
START
> 3.5V
YES
YES
VCORE=1.2V~1.5V
1V88_VMEM=1.88V
2V93_VEXT=2.93V
2V5_VMIC=2.5V
YES
HIGH(above 1.2V)?
YES
YES
The phone will
NO
Charge or Change Battery
NO
Check the contact of power key
Or dome-switch
NO
Replace U102
2V75_VCXO=2.75V
2V85_VSIM= 2.85V
1V5_VPLL=1.5V
2V5_VABB=2.5V
NO
Re-download software
NO
Replace U102 and Re-download software
Does it work properly?
Replace the main board
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
- 68 - Copyright © 2009 LG Electronics. Inc. All right reserved.
NO
Only for training and service purposes