Check the battery voltage across to the components highlighted on the solution below. These are filter coils and you need to have a voltage reading in this components about 3.7 volts., It is connected directly to the battery positive terminal. Replaced filter coils if found damaged, apply a jumper wire if found the supply voltage line is open or cut.
5320 No network problem solution 1- RF Supply Voltage
Check the voltages in these components highlighted in below solution, these are the output voltages from the voltage regulator chips that supplies to the RF IC and RF Power Amplifier chip. If there is no voltage readings in these components, check and replace the corresponding Voltage regulator chip.
5320 No network problem solution 2- RF regulated supply voltages
1)Rework or replace the Power amplifier PA IC,
2) Replace the Voltage controlled crystal clock oscillator
3) Rework the RF IC or replace if necessary