No Power On--Small Current - Huawei U8800 Maintenance Manual

U1001 CHG_CHIP /
VPH_PWR-test
U1001 3.7V
L1001
VBAT-test 3.7-
U3501
C3501 4.2V
VBAT-test 3.7-
U3302
C3302 4.2V
Q301 MOSFET /

9.2.2 No Power on--Small current

Analysis：
The current is among 10mA-500mA scope as power supply by DC-power. The problem of software or
FLASH causes the failure usually. Reference Figure 9-2
2011-03-21
U8800 Maintenance Manual Basic Version V1.1
U3501
U3402 U3302
VCC-test
U3402
C3406
Huawei confidential. No spreading without permission.
J1102
U301
3.7-
4.2V
U201
Figure9-1
Internal
Pin1-test
J1102 5.0V
LB1101
VPH_PWR-test
U301 3.7V
C409
3.7-
J1501 Pin3-VBAT
4.2V
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