LG -A290 Service Manual page 71

START
Check
Battery Voltage
> 3.35V
Push
power-on key
And check the level change
into high of POWERKEY
Check
the voltage of
The LDO outputs at U101
Logic
level at RPWRON of R116
= HIGH(above 1.V)?
the phone power on?
The phone will
Properly operating.
LGE Internal Use Only
Yes
Yes
Yes
Yes
Is
Yes
No
No
Check the contact of power key
No
VCORE_PMU = 1.V, VTCXO = .8V. VRF = .8V, VA =
.8V, VM = 1.8V, VIO = .8V, VCAMA = .8V, VUSB =
3.3V, VSIM1 = 3.0V, VSIM = 3.0V, VHP_1V8=1.8V
No
No
- 71 - Copyright © 01 LG Electronics. Inc. All right reserved.
4. TROUBLE SHOOTING
Charge or Change Battery
Or dome-switch
Replace U101 (MT653)
Re-download software
Replace U101 and
Re-download software
Does it
work properly?
No
Replace the main board
Only for training and service purposes