Huawei U8650, Maintenance Manual

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U8950 Maintenance Guide V1.0 9 Maintenance Records During Verification
2012-10-22 Huawei Proprietary and Confidential 43
Stage Station of Fault Faulty Item Symptom Solution
VN1 MMI MMI03A key
malfunction The shrapnel of the
volume up key was
deformed and could
not contact the
volume key FPC. The shrapnel of the volume up key
was adjusted.
VN1 MMI MMI02C
microSD card
detection
failure The microSD card
was faulty. The microSD card was replaced and
the test then passed.
VN1 MMI
MMI02C
microSD card
detection
failure The microSD card
slot was poorly
soldered. The third pin of the microSD card
was not soldered using sufficient
solder had no resistance. The
problem was retained as it occurred
for solder-printing analysis by the
R&D and process departments.
VN1 MMI MMI02C
microSD card
detection
failure The microSD card
slot was poorly
soldered and no 1.7
V voltage output
was detected on the
pin. The microSD card slot was not
re-soldered since the CPU was right
on the front and heating the slot was
risky.
VN1 MMI MMI02C
microSD card
detection
failure The Dat0 signal of
the microSD card
slot's 7th pin was 42
ohm (normally it
should be 4 Mohms).
It was determined
that the filter U1402
was short-circuited. It was determined according to the
batch number of this task order that
the filter U1402 was short-circuited.
The problem was retained as it
occurred for further analysis by the
process department since the board
had been through the silica gel
dispensing.
VN1 MMI MMI02A The SIM card is
defective. Replace the SIM card.
VN1 MMI MMI02A 1 pin of the SIM
card holder was
missing. Take a photo of the card holder and
give feedback to the vendor.
VN1 MMI MMI02A No reset signals on
the SRST pin. Replace the pin.
VN1 MMI MMI01F LCD defects
Keep the defective LCD and conduct
further analysis.
VN1 MMI MMI01F LCD defects Keep the defective LCD and conduct
further analysis.
VN1 MMI MMI01F LCD defects Keep the defective LCD and conduct
further analysis.