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8. Level 3 Repair
8-4-1. Power On
Mobile phone does not power on.
Yes
No
No
Charging the battery by TA.
If its voltage level is extremely low
(under 3.0V),
Change the battery.
Yes
No
END
Yes
No
Power-on the phone and check
the power-on sound
or motor Vibration.
Sound or Vibration is ok?
Yes
Change the FRONT-LCD ASSY
No
Check the voltage level at
R5025 while pressing power
key. Is the voltage high?
No
Replace the Power key FPCB
Yes
No
Check the signal of XPSHOLD
= 1.8V
No
Check the output voltage of U5002
L5012=1.8V, L5007=1.3V, C5000=0.8V, C5007=0.8V,
C5008=0.8V, C5009=0.8V, L5004=0.8V, L5002=0.8V,
L5001=0.8V, L5009=0.8V, C5020=1.0V, L5005=0.8V,
C5002=1.8V, C5010=0.8V, C5004=0.9V, C5011=0.9V
If the output voltage is not normal, Change the U5002
※
Each voltage level has ±10% margin.
Yes
No
Check the Clock U2004
Is the frequency 19.2MHz?
No
Replace the U2004
※
Test condition (Oscilloscope setting)
: 20.0us.div (time division)
Yes
No
Check the initial operation
Check the Battery Voltage.
Is it more than 3.5V?