LG lg-d821 - Page 179

3. TROUBLE SHOOTING
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3.19.1 Power ON Troubleshooting (MSM8974)
Battery voltage
higher than 3.3V?
Change or charging the Battery
No
Yes
Check SDRAM(U5000) And eMMC(U5001)
Press PWR Key
TP : R11010
Come high to low?
Yes
Yes
Yes
Check PM8941
Vreg xx level
Check PM8841
Vreg xx level
Check PM8941 (U6002)
Check PM8841 (U7000)
Check Power Key,
Pin 1 of KBR11000
No
Start
Yes
Yes
Yes
Yes
Yes
Yes
PON_OUT pin
Of PM8941 is High? (1.8V)
PON_RESET_N pin
Of PM8941 is High?(1.8V)
Check Main Clock
TP : X6000 (19.2MHz)
SMPS_1B,2B of
PM8841 is high?(more than 0.9V)
VOUT pin U6000
Is battery level Or more than 3.5V?
PS_HOLD pin
Of MSM8974 is High?(1.8V)
No
No
Check PM8941 (U6002)
Check PM8941 (U6002)
Check PM8941 (X6000)
Check PM8841 (U7000)
Check Bypass Boost (U6000)
Check MSM8974 (U3000)
No
No
No
No
No
No