LG Electronics LG-C320 service manual Power on Troubleshooting, Start, Than 3.20V? Yes

4. TROUBLE SHOOTING

4.TROUBLE SHOOTING

4.1Power ON Troubleshooting

Power On sequence is :

PWR key press PM_ON_SW_N Î QSC6270 KPDPWR_N pin(AA2) go to low(Main BOARD R205) Î QSC6270 Power Up Î VREG_MSMC_1.2V(C261), VREG_MSME_1.8V(C209), VREG_MSMP_2.6V(C414), VREG_RFRX2_1.3V(C232), VREG_TCXO_2.85V(C275) power up and system reset assert to QSC6270 Î Phone booting and PS_HOLD assert to QSC6270

START

Battery voltage. higher	No
than 3.20V?
Yes
Replaced	Yes
with normal LCD module,
and then Booting is OK?
No	No
TP1_R205 go to low
When Power key press?
Yes

TP2_VREG_MSMC_1.2V(L201) No TP3_VREG_RF1_2.3V(L202) TP4_VREG_RF1_1.4V(L203)

power up? Yes

Change or charging the Battery

Go to LCD Troubleshooting

Check the Key Dome

Change the main board

Change the main board

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