No Power On-Small Current (Dc Power Supply) - Huawei E5331 Maintenance Manual

9.2.2 No Power On—Small Current (DC Power Supply)
Reference Figure 9-2
U201 Output
VDD_2V6
LDO5
VDD_PMU
V_CORE_1V8
VREF
VDD_2V8
VBUCK5
2012-4-21
E5331 Maintenance Manual Basic Version V1.0
Small Current
Download the
latest software version, check
whether it is normal?
N
Measure whether
output signal value of the X3501
is normal?
Y
Measure whether
output voltages of the U3501 are
normal?
Y
Replace U3201, check
whether it is normal?
N
Replace the U3101
Reference Value
Huawei confidential. No spreading without permission.
Y
Replace the
N
Replace the
N
Y
2.6V
/
3.1V
1.8V
2.6V
2.8V
2.85V
End
X3501
U3501
End
Test Point
C3512
C3507
C3533
C3505
C3514
C3511
C3521
Internal
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