Huawei YU220, Service Manual

Page: 33 / 66

YU220 service manualV1.0
2013-10-18
Huawei secrets, no dispersion without permission
For several other main power short circuit phenomenon, refer
to 5.1.2 analytical process to determine whether these power shorted to
ground, the processing method is to remove several inductors L501, L502, L503,
and testing the two PAD inductive impedance to
ground If the PAD near PMIC shorted to ground, which means that the
PMIC bad, on the contrary, it means the back of a short circuit inductance
.
In brief, for L501 inductance, if close to PAD of PMIC over the ground short
circuit, it can judge PMIC bad, if another PAD short circuit, it can see link to CPU
from internet, CPU bad, this phenomenon is in the majority.；
For L502 inductance, if close to PAD of PMIC over the ground short circuit,
it can judge PMIC bad, if another PCD short circuit, it can see U202，U203
linked to internet bad.