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8. Level 3 Repair
8-4-1. Power On
Mobile phone does not power on.
Yes
No
Yes
Change the FRONT-LCD ASSY
Replace the Power key FPCB
Yes
No
Check the signal of
TRST_N = 1.8V
No
Check the output voltage of U5000
L5000 > 0.75V, L5001 > 0.75V, L5002
> 0.75V,
L5003 > 0.75V, L5004 > 0.75V, L5005
> 0.75V,
L5006 > 0.75V, L5008 > 1.1V, L5009
> 1.3V, L5010 > 2.0V, L5011 > 0.75V
and other LDO Voltage
If the output voltage is not normal,
Change the U5000
※
Each voltage level has ±10% margin
Yes
No
Check the Clock OSC5000
Is the frequency 32.768kHz?
No
Replace the OSC5000
※
Test condition (Oscilloscope setting)
: 20.0us.div (time division)
Yes
No
Check the initial operation
Yes
No
No
Charging the battery by TA.
If its voltage level is extremely low
(under 3.0V),
Change the battery.
END
Yes
No
Power-on the phone and check
the power-on sound
or motor Vibration.
Sound or Vibration is ok?
No
Check the voltage level at
R50122 while pressing power
key. Is the voltage high?
No
Check the Battery Voltage.
Is it more than 3.8V?