Hey Stefan, thanks for your reply. I found another post somewhere, where somebody recommended to replace the Wifi daughterboard, as you did. Another person answered:
“No! That is not what you need to do. This is the GSM antenna, nothing to do with WiFi. If your WiFi is greyed out (Can’t switch it on) or switches off itself after switching it on, you have a problem with the WiFi chip. If it switches on but you have no WiFi reception, it is the antenna circuit which is broken. (Also often the WiFi chip). The good news is, it can be repaired. The bad news is, you will need to find someone who can do it for you if you dont have the skills.
The upper right ground shield needs to be removed for the repair.
Here you see the WiFi / Bluetooth / GPS chip on the upper right side.
https://d3nevzfk7ii3be.cloudfront.net/igi/qqgKRTUPEeD3dRhG.medium9
To repair your board, all pins need to be reflowed. Fortunally this is not a BGA (contacts underneath) so it can be resoldered on all sides. Once this is done, there’s a very big change that your FP1 is fully operational again. I have done some of these boards and they all had their Wifi / Bluetooth / GPS back. If you consider repair, make absolutely sure that the person performing the repair is skilled enough! I have seen enough horror results from people that 'knew what they were doing”
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the link: FP1 Wi-Fi connection doesn’t turn on
what do you think about this?