Network Fault in mobile (n91 and 6131), no network solution

Network fault is a major fault in nokia mobile. This can be due to two major reasons:

• A. Hardware problem (like physical damages and water damage)
• B. Software problem

First we consider hardware problem in nokia mobile below.
Types of fault:

1. No network in mobile:
Description:
In some case mobile have no network when we manually search or set automatically mode.
This fault mainly due to hardware problem (in 75% cases) & in rest of cases this fault due to software error.

Solution:
1. First manually search network if any operator found but failed to register then check network antenna switch then use following tips:

• A. Firstly heat over antenna switch section
• B. Then apply antenna jumper same as in below image :-

Jumper :- Jumper is a bypass technique to work like antenna switch .jumper connect two or three point of antenna switch .

• C.If problem persists then replace the network antenna switch.

2. In case when we manually search the network and no network found then check 

“PFO (power frequency oscillator)” sometime called PA.
Below is image of nokia 6131 pfo (pa)

• A. First clean the pfo with acetone or white petrol then heat over pfo section
• B. If problem persists then reball the pfo
• C. If problem still persists then change the pfo.

Conclusion:

To repair network problem due to hardware reason we have to consider just two main component pfo and antenna switch to repair properly network problem. For this you should follow all instruction step by step. If we properly make right diagnosis and follow all instruction then our network problem will be 100 % solved.