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4. Trouble Shooting
4.9 Power ON Troubleshooting
Power On sequence of GT540 is :
Power key press
Æ
KPD_PWR_N(VA20) go to low
Æ
PM7540 Power Up
Æ
VREG_MSMC1_1.2V(C104),
VREG_MSMC2_1.2V(C107), VREG_MSME_1.8V(C161), VREG_MSMP_2.7V(C106), VREG_MSMA_2.6V(C109),
VREG_TCXO_2.85V(C218) power ON
Æ
Phone booting and PS_HOLD(D18) go to High
START
Battery voltage higher than
3.70V(OCV)?
Change or charging the Battery
No
Yes
Redownload SW image
TP1 hight to low when key pness?
Check correctly working powerkey
No
Yes
TP2(1.2V), TP3(1.2V), TP4(1.8V),
TP5(2.6V), TP6(2.6V), TP7(2.85V)
power up currently?
Change the Main board
No
Yes
is clock OK?
TP8:19.2M
TP9: 32.768Khz
Change the Main board
No
Yes