This instrucstion is only for model Ipad Air 2 with 3G-module. After applying of it you will get ipad Air 2 Wi-Fi , but WiFi, Bluetooth willn’t Work on stock firmware.
To enable WiFi you need iOS with jailbreak to replace some files.
If you can find instructions for other models of ipad: Here
iPad Air 2 - 4G has IMEI on back side. Model A1567 – GSM .
Intruction for unlocking
Warning! Be careful. If you are unsure of your skills , entrust this work to professionals. Good luck!
Disassemble your tablet. Disconnect the battery . Take out the motherboard.
Now we have to find resistors responsible for boder_id. Remove them, you will turn off the modem and change identity of your iPad.
1. On Model A1567 (GSM) make jumper on marked place.
2. Tablet enter DFU mode.
3. Connect the tablet to your PC or Mac.
4. After that you need to restore the tablet through iTunes with firmware of Wi-Fi model and activate using the official method.
5. Turn off the automatic firmware update : Setting\ iTunes Store, App Store\ Automatic download\Updates.
Enabling WiFi and Bluetooth on iOS 9
1. Download file: Here
2. Install iOS 9 on iPad Air2.
3. Do jailbreak, install Cydia.
4. Connect iPad to internet though Bluetooth on phone.
5. Download and install iFile and afc2add from Cydia.
6. Open ifile on iPad Air 2.
7. Go to directory “usr/share/firmware/wifi/C-4350 __ s-C2/’’. Backup all file there and replace them by files archive.
Reload iPad Air 2.