Mobile Phone Xolo Mirage Plus (Smartphone)
Service Manual
Page
30
of 40
PC can‟t recognize the phone
Change for another download cable and try again. Otherwise, you need to check whether the
PINs of the system interface are broken. If everything is ok, please re-solder or replace the
corresponding I/O connector and baseband CPU.
Download tool hangs when downloading
You need to check the corresponding FLASH chip, baseband chip and trace between
baseband CPU and FLASH.
4.15 Signal issue analysis
Signal
failure
Repair RF circuit
End
Y
Is RF parameter normal
Re-calibrate RF
Is RF ANT normal
Replace RF ANT
N
Y
N
Upgrade firmware
Figure 4.15 Signal failure repair process
RF failure often occurs in calibration or capability test, the best diagnostic method is to use
wireless universal tester, spectrum analyzer and signal source matched with META tool to test it.
Corresponding components including: Antenna switch, Saw filters, matching circuit etc. We need
to check whether one of them is bad soldering or damaged. If power received is too low maybe the
RF circuit is cut off, you need to check saw filter, matching circuit, antenna switch, and control
signal etc. If the bit error is too high, it maybe because of the saw filter is not qualified.
