The customer sent us an iPhone 7. The fault description is iPhone 7WIFI, Bluetooth cannot be turned on, and there is a leak.

After receiving the iPhone7, after testing, we found that Wiif could not be opened, but Bluetooth could be turned on and the compass had problems. How to fix this problem?

First set the backlight to the brightest and the screen to dark. Based on our past maintenance experience, we believe that damage to the general functional modules can lead to leakage and rapid power consumption. Since the Wifi function cannot be activated, it may be caused by damage to the iphone Wifi IC.

Disassemble the iPhone, use DC Power supply to power on, indicates that the current is missing, trigger more than 100 jumps. Then open the motherboard with QUICK 861DW Hot Air Rework Station we discover it is a water machine, but before that, the customer didn't tell us .

Observe the iPhone under stereo zoom microscope and see that there is corrosion next to the Wifi. Maybe this is where the fault lies.

Clean corroded area with wash water, and remove corroded filter capacitor, then connected to DPS DC power supply, the current starts to jump from 100 hops. So the problem still exist. We check other places and found a small capacitor under the compass that was corroded and damaged. Use digital multimeter to measure the voltage, there is a short circuit condition. Is this the reason of error?

Remove the capacitor directly, measure the resistance value with a digital multimeter, and the resistance value is normal. It is also right after power-on. Install the motherboard and test, Wifi can be turned on, and the compass is back to normal. So dark backlight is due to screen. Fault have been removed, this repair work is over!