Just bought a used Iphone 3gs 3.1.3 original unlocked.
But there is something wrong with the WiFi.
In settings the WiFi is grey and just says "No WiFi".
Can't touch the WiFi or do anything.
Tried reseting the phone a couple of times using iTunes but no luck.
Also tried reseting networksettings without any change.
Standard troubleshooting steps in the following order:
1. Power the iphone off, then back on.
If no change, continue:
2. Reset: Press the sleep/wake button & home button at the same time, keep pressing until you see the apple logo, then release. Ignore the slide to power off. No saved data or settings will be lost.
If no change, continue:
3. Restore your phone from your most recent backup, Note, however: if the problem is related to corrupt data in your phone's backup, while this will restore a fresh OS, it will also restore the problem.
If no change, continue:
4. Restore as a "new" phone in itunes & re-sync your content. All saved data will be lost.
If no change, make an appointment at an Apple store, as you most likely have a hardware problem. There are no more user troubleshooting steps available.
This almost always is a hardware failure in the WiFi circuit. The only fix is replacement. Since a 3GS should still be under warranty, take it to your carrier (Apple doesn't provide tech support in Sweden).