Here is an iPhone 7 is damaged by dropping, luckily, the iPhone 7 still can turn on, unfortunately, the iPhone WIFI button is grayed out and won't turn on, which means the iPhone 7 WIFI function can't be worked! Here to get the solution to fix it.
Firstly, use phone opening tools to disassemble the iPhone 7, and then take out the iPhone motherboard. As we know, the iPhone 6S and later, the iPhone WIFI IC was bound to iPhone Nand flash. Because this is drop-damaged iPhone 7, so first we need to check iPhone WIFI IC, instead of removing iPhone Nand flash.
Before we remove the iPhone WIFI IC, we need to protect the iPhone CPU. Use High Temperature Resistant Tape to cover the iPhone CPU, and then use QUICK 861DW hot air rework station to heat the iPhone WIFI IC, and then remove it.
After remove the iPhone WIFI IC,we can see that there are 2 pieces useful pins are dropped. The 19 pin and 22 pin on the left side is dropped, and 20 pin almost dropped.
For the 19 pin and 20 pin, they can be found the connection point on the left side, so we can solder the jumper wire. For the 22 pin, we need to solder the jumper wire from C0811.
Put iPhone motherboard under the Stereo Trinocular Microscope to check four grounding pins, they are not connected, which means the pins that connected to the ground also will virtual welding, in resulting iPhone baseband power supply voltage directly send to the iPhone baseband CPU, the voltage is too higher, and then burned internal of the iPhone CPU.
When we replace the iPhone baseband power, if the baseband circuit tested is normal, then we can connect these 4 pieces grounding pins. After finish the jumper wire welded, use digital multimeter to measure the resistance value, the value tested is normal.
Now, install the iPhone CPU back the iPhone motherboard, and then use DPS DC power supply to check whether there is shorted circuit issue. Because the shorted WIFI bus will burn the iPhone CPU.
After testing, the current and voltage are normal. Test the iPhone WIFI function, it works perfectly.



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