Power On Trouble - LG GW520 Service Manual

5. Trouble shooting

5.2. Power on trouble

Start Start
Battery Voltage, higher Battery Voltage, higher
Than 3.35V? Than 3.35V?
32.769KHz clock at 32.769KHz clock at
X100 `is ok? Click TP1 X100 `is ok? Click TP1
26MHz clock at U504 26MHz clock at U504
is ok? Click TP2 is ok? Click TP2
PWRON pin(TP3) is high PWRON pin(TP3) is high
Before push the end key? Before push the end key?
PWRON pin(TP3) is low PWRON pin(TP3) is low
when push the end key? when push the end key?
LDOs output(C210, C211, LDOs output(C210, C211,
C212 C215,C219, C220, C221, C212 C215,C219, C220, C221,
C222, C223, C224, C225, 226, C222, C223, C224, C225, 226,
C227,C228) of U200 while C227,C228) of U200 while
push the end key is ok? push the end key is ok?
Power on is ok? Power on is ok?
END END
LGE Internal Use Only
YES YES
NO NO
YES YES
NO NO
YES YES
NO NO
YES YES
NO NO
YES YES
NO NO
YES YES
NO NO
YES YES
NO NO
GW520 service manual
Change or Charging Change or Charging
the Battery. the Battery.
Check soldering Check soldering
or change X100 or change X100
Check soldering Check soldering
or Change U504, X500 or Change U504, X500
Resolder R203,208 Resolder R203,208
Check KeyPCB's dome sheet Check KeyPCB's dome sheet
or NO.18 pin of CN400 or NO.18 pin of CN400
Check soldering or change Check soldering or change
U200 and relevant component U200 and relevant component
Change the main board Change the main board
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