Mobile Phone Xolo Mirage Plus (Smartphone)
Service Manual
Page
16
of 40
Chapter 4: Mobile Failure Analysis
Basically, MIRAGE PLUS main failure cases including:
Power on problem (No power on, Auto-Power on/off, Phone totally dead, Restart
automatically)
Display failure (No display, LCD backlight malfunction, Segments missing, Black display,
and Contrast malfunction)
Signal problem (No signal, Weak signal, No signal intermittent)
Charging problem (No charging)
Call problem (Call drop, No incoming audio, No outgoing audio, Cannot receive call,
Cannot dial out, Bad voice quality, and Low receiving volume)
Other Function problem ( No ringing tone, No vibration, Vibrator abnormity, Clock fault,
Cannot read SIM /T-F card, Phone password locked, Cannot upgrade software, Show "high
temperature", FM Radio fault, Touchscreen issue, Bluetooth issue, Camera issue, Wi-Fi
issue, etc.)
In the mobile circuit system, all the electrical connecting trace can be divided into three types,
such as power supply trace, controlling trace and signal trace. When analyzing the RF failure case,
for the active circuit we should first check the power supply, then control circuit followed by the
signal flow path to remove the failure step by step. When debugging the RF malfunction, we
should diagnose the RX part first before TX.
