Basically due to the upgrade of software made by Apple to iphone, older models of iphone with higher baseband cannot penitrate to get the signal of mobile networks. As what we know is that once we purchase a mobile, we can use it at anyway and at anyplace (which is suppose to be like that). However, due to the upgrade and designs of new hardware it might be unintentional made by iphone (apple co) to do some upgrade on software and might not consider the disturbance function of older iphone models, the result may vary to the user to purchase a new iphone models or downgrade your software.
Marketing strategy can be considered as another cause of malfunctioning mobile that suppose to have a longer life span especially for expensive ones.
The second reason why iphone 3gs users experience this issue "Iphone 3gs No Signal, No Service and Searching Issue" it is because the mobile is locked to a specific network, the solution is to unlocked it.
Either of 2 issues above mentioned can be fixed but needs some experties or some trials/practice in order to achieve the success of unlocking your iphone 3gs or downgrading. In my blog i will show the step by step process to solve to issue. I might be posting at daily basis but just remember the issues:
1. Upgrade Issues - make sure that your iphone 3gs is openline when you purchace long time ago. If it is new and the box is opened in front of you or your are the only person who opened it means that it is an open lined from the seller itself. However, if is used or the open and inserted in a PC chances that is is locked and they just unlocked it.
During your upgrade to the versions from 5.0 til 6.1.3 the chances of loosing your network is at high since the software baseband of iphone 3gs after before week 48 of 2011 cannot penitrate to have its upgraded software, however, some iphone 3gs that has been manufacture after week 48 of 2011 can work normally but cannot be jailbroken after sometime. For iphone 3gs manufacture before week 48 of 2011 you can downgrade your software version of baseband as well using legal way or illegal way. I will show the advantages and disadvantages of both options in my later post.