Yesterday, we got a iPhone 6, which fault is no service after dropping. It has no IMEI on the LCD screen when we input *#06# on the keypad, and it can't search the operator when we insert the SIM card. Vip Pro Shop Team can give you solution.
Base on the faulty description and
according our experience, we can make sure that the service error was caused by
RF circuit part. Now, we need to fix it step by step.
1. Disassemble the iPhone 6 with screwdrivers, carefully remove the motherboard.
2. Using multimeter to measure the diode data of testing point
PP3172_RF, the result of value is 0. The near place of it is U_DSM_RF,
U_HBS_RF, U_ASM_RF, MDM9625M and U_FFER. We can check it in the Schematic Diagram, as shown in picture 7-13-2, 7-13-3,
7-13-4, 7-13-5.
3. Because we are not sure which chip is
causing a short circuit error, so we need to tear down the adjacent chips and test
it. We’ve removed several adjacent chips, but the short circuit error still
exists, until we tear down the U_BUFFER, it doesn't show a short circuit fault
when we measure it with multimeter. As shown in picture 7-13-6.
4. Replace the new U_BUFFER IC on it, and
assemble the chips that were removed. Then reload the iPhone 6.
Finally, power on iPhone 6, when we input
*#06#, the IMEI appears on the LCD screen. When we insert the SIM card,
the signal is back, and it can make the phone call normally. The iPhone 6 was
repaired!
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