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Solution: iPhone 8P No Service After Inserting SIM Card


We received iPhone 8 from our customers, the problem was that iPhone 8P dropped before, then iPhone 8P was inserted into the SIM card and had no service. If we did not insert the SIM card, iPhone always prompted "no SIM card installation". How did this happen? Let's check the solutions in this article!

For dropped iPhone, most of the iPhone pad pins are lost, or iPhone drops short circuited. IPhone 8 Plus was discarded before, so we suspected that the pad was dropped from the pin.

After we untied the iPhone, we found that iPhone had been repaired by other maintenance personnel, and the DSMLLBYE and DSMHBHE chips on the iPhone motherboard had been removed.

Use Fluke 15B+ Digital Multimeter to measure the diode data for iPhone solder pad, we found the SCLK_HB_LB_DSM_FILT_E signal for the DSM_LB_E and DSM_HB_E IC is short-circuited.

Open the WUXINJI Dongle to check iPhone schematic diagram and bitmap, we found the previous repair man installed the R1608_E resistor in the C1602_E capacitor position, the position of the C1602_E capacitance on the schematic diagram is not installed.


Use tweezers to remove the resistance on the C1602_E capacitor position, and then use QUICK861DW to solder it to the original place, solder the jumper wire to the missing pins on the solder pad, and welded the component chips. Now install the iPhone and test it, but the problem still there.

Disassemble the iPhone, observe the iPhone motherboard under the 3D Digital Microscope, comparing with the iPhone schematic diagram, we found the FL1501_E inductance missing, but it's installed on the schematics diagram.


Connect the missing inductor directly，and then turn on the iPhone to test.


Now the signal is normal after insert the SIM card, and the phone call is normal, the repairs end.

This failure is caused by missing pins on solder pad and dropped components

If you need any other professional cell phone repair tutorials, please contact us on www.vipfixphone.com

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