Micromax Q427+ - GPS cannot locate and open; GPS Location Troubleshooting

Q427+ L3 Service Manual
 Check the BT/WIFI/GPS/FM Chip normally or not, then Re-Solder Power IC or change it.
 Check the CPU normally or not, then Re-Solder CPU or change it.
24. Network issue:
Solution:
 Flash the handset with latest SW
 Check the RF Antenna Slot soldering quality, if not, Re-sold it or change it.
 Check the RF coaxial line normally or not. Re- Assembly it or change it.
WiFi/BT
/FM/GPS ANT
CPU
Bt/WiFi/Gps
/FM Chip