Huawei G700-U10 Maintenance Manual page 40

G700-U10 Smartphone
Maintenance Manual
Figure 10-7 Troubleshooting excessive current startup failures
Circuit Signals
Table 10-1 Circuit signals of this section
Signal
VBAT
VCORE
VAPROC
VDD18
Issue 1.0 (2013-07-22)
Startup failure
Connect the phone to a fake
battery and maintenance power
supply, power on the phone,
and observe the current
Excessive
current
Is VBAT short-
circuited to the
ground?
N
Are the VCORE,
VAPROC, and VDD18
short-circuited?
N
Resolder or replace
U202
Description
Battery voltage
Digital core voltage
Processor voltage
I/O voltage
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10 Circuit and Failure Analysis
Y
Replace the faulty
component
Y
Replace the faulty
component
Reference Value or Waveform
3.2 V to 4.2 V
1.1 V
1.2 V
1.8 V
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