Micromax Q427+ - BT is not working fine; Bluetooth Troubleshooting

Q427+ L3 Service Manual
 Check BT 11 to 30 S if these are working fine。
 Flash the handset with latest SW
 Check the BT antenna normally or not, then Re-Solder or change it.
 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.
19.Keys are not working:
Solution:
WiFi/BT
/FM/GPS ANT
CPU
Bt/WiFi/Gps
/FM Chip