Charge Failure - Huawei Mediapad S7-PRO Maintenance Manual

9.3 Charge Failure

The Mediapad charging management circuits are shown in the following figure.
Principle: The DC regulated power supply provides the 5 V/3 A power supply to the DC-DC
circuits in the MAX8903, and MAX8903 and the power is output through VBAT and
VPH_PWR respectively.
Analysis: The U48 manages the charging of S7 Pro. For the maintenance procedures upon
charge failure, see the Appendix 1 (diagram of PRO components).
2012-07-20
S7-PRO Maintenance Manual (Basic Version V2.1)
Power-on fails due to low current
Check the U48 output and
measure whether the voltage
difference between C665 and
C624 is 4.2 V
Yes
Check the U7 output and measure
whether the voltage difference
between C418 and C419 is 1.8 V
Yes
Perform eMMC programming
again (U12)
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No Replace U48
No Replace U7
INTERNAL
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