LG D405 Service Manual page 109

Press PWR Key TP1: R9607
Come high to low?
Check Main Clock TP2:X4100 (19.2MHz)
Check BBCLK TP3:R4110
Check PM8226's VREG_S1 is high
PON_RESET_N high?
PS_HOLD (TP6:R4104)
Check battery connector &
+VPWR line filter(CN9100,FL9100)
LGE Internal Use Only
START
Battery voltage
higher than 3.3V?
Yes
Yes
Yes
Yes
(0.7V) TP4: C4139
Yes
TP5:TP4103
Yes
Yes
No
Change or charging the Battery
No
Check Power Key(SW9711)
No
No
Check U4100(PM8226)
No
Check U4100(PM8226)
No
Check U4100(PM8226)
No
Check U4100(PM8226)
- 109 - Copyright © 2014 LG Electronics. Inc. All right reserved.
3. TROUBLE SHOOTING
Check X4100
Only for training and service purposes