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PC can't detect USB COMPORT. Check your device manager for COM Qualcomm
QDLoader 9008. If not, please check:
1.
Check the power supply/battery (4.2V)
2.
Make sure all fixture pins contact well, also check the connection of the IOFPC
and Sub board
3.
If heavy current occurs when booting up, probe VBAT (T9603 or T9602) and
VPH_PWR (C2402.1 or C2402.1) and search for short circuits.
(1) VPH_PWR shorts to
NFC Power U5402, BL driver PU8901, Audio codec AU2601, Vibrator AMP
U2401.
4.
If system shuts down before booting up, check MSM_RESIN_N (T8702) if the
TP is high (1.2V). Check which power in the PON sequence ended.
(2) VREG_S2A, S8A, S9A, S3C abnormal impedance:
MSM(U0201), PMIC(PU8401, PU9701) to search for short circuits. If not, try to
reheat or remount DDR.
1001 Provision check fail-DL
GND: X-ray check PMIC
PU9701 & PU8401 &
Check both DDR &
PU9001,
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