Repair Guide: WiFi cannot be opened after iPhone 7 is dropped on the ground
We received an iPhone 7, the fault description is that the iPhone was once dropped, and the WiFi cannot be opened after the screen is replaced. Where did the fault occur? Please read below.
He took the phone to my store for repairs. Unpacking the phone, I saw no signs of repair on the motherboard, and in general, starting with the 6S machine, WiFi is tied to NAND Flash. And because this machine has been dropped before, so we will not shake the NAND flash, we need to protect the CPU and remove the iPhone WiFi IC.
Wrap wice with wipe in the CPU position, then wrap around a few circle with the foil. This method is near no problem. After disassembled, two useful points drops from the pad drops .
Wrap wice with wipe in the CPU position, then wrap around a few circle with the foil. This method is near no problem. After disassembled with QUICK 861DW Rework Station, two useful points drops from the pad.
19 and 22 pin on the left side are dropped directly. 20 pin is nearly dropped down. 19 20 pin can find the connected points from the left side, just need weld a extra wire. The 22 pin require solder iPhone jump wire from the C0811.
we found the epidermis of this 4 grounding point isn't connected at all when observe under the Stereo Zoom Microscope, that is, the grounding pin is also exist pseudo soldering, which caused to the baseband power supply portion can't form closed circuit. And the voltage is applied to the baseband CPU directly, too high voltage burn the internal baseband CPU.
When replace the new baseband power supply, if there is no problem after tested the baseband line, you can string the four grounding points at first. From now, we tested some Qualcomm machine , and we found there is no problem treated with this methods.
After welding the line and curing, measure the sole value with digital multimeter, if it's normal , install the WiFi IC, and be sure to use the power meter to check if there is a short circuit for WiFi total line may burn out the CPU.
Now, power-up and test, the function is normal, the iPhone 7 white WiFi repair completed successfully.
He took the phone to my store for repairs. Unpacking the phone, I saw no signs of repair on the motherboard, and in general, starting with the 6S machine, WiFi is tied to NAND Flash. And because this machine has been dropped before, so we will not shake the NAND flash, we need to protect the CPU and remove the iPhone WiFi IC.
Wrap wice with wipe in the CPU position, then wrap around a few circle with the foil. This method is near no problem. After disassembled, two useful points drops from the pad drops .
Wrap wice with wipe in the CPU position, then wrap around a few circle with the foil. This method is near no problem. After disassembled with QUICK 861DW Rework Station, two useful points drops from the pad.
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19 and 22 pin on the left side are dropped directly. 20 pin is nearly dropped down. 19 20 pin can find the connected points from the left side, just need weld a extra wire. The 22 pin require solder iPhone jump wire from the C0811.
we found the epidermis of this 4 grounding point isn't connected at all when observe under the Stereo Zoom Microscope, that is, the grounding pin is also exist pseudo soldering, which caused to the baseband power supply portion can't form closed circuit. And the voltage is applied to the baseband CPU directly, too high voltage burn the internal baseband CPU.
When replace the new baseband power supply, if there is no problem after tested the baseband line, you can string the four grounding points at first. From now, we tested some Qualcomm machine , and we found there is no problem treated with this methods.
After welding the line and curing, measure the sole value with digital multimeter, if it's normal , install the WiFi IC, and be sure to use the power meter to check if there is a short circuit for WiFi total line may burn out the CPU.
Now, power-up and test, the function is normal, the iPhone 7 white WiFi repair completed successfully.
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