How to Fix iPhone 6S No SIM Card - Hardware Solution

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After inserting the SIM card, turn on the iPhone 6S and display no SIM card. First, we test whether the SIM card is faulty, remove the iPhone SIM card and re-seat it, update iOS, check for an iPhone carrier settings, but the iPhone still doesn't recognize the SIM. We think the SIM card could have a hardware problem. Let's disassemble the iPhone 6S to check the iPhone hardware.

Use phonefix screwdrivers to remove the screws next to the iPhone lighting port, put the iPhone 6S on the Screen Separating Machine. After heating for a while, use LCD sucker and pry tools to remove the iPhone display assembly. Disconnect the iPhone battery, and then take out the iPhone 6S motherboard.

Measure the iPhone 6S SIM card slot with digital multimeter, the resistance valued measured is normal, and both the SIM card power supply and plug-in SIM card detection has 1.8V voltage when measuring, which means the iPhone 6S no SIM card problem is caused by other reasons.

Continue to measure the iPhone motherboard, when measured 75_RFFE2_SDATA_BB, we found the Bus is short-circuited.

Log into the ZXW online dongle to check the iPhone 6S schematic diagram, this circuit is connected with many chips.

For the short circuit problem, generally there are 2 methods, one is remove the components one by one until the short circuit part is found, and the other one is rosin method. Because it's signal part, so we'd better not use rosin method.

Put the iPhone motherboard on the PCB holder fixture, and then use hot air gun and tweezers to remove the related components one by one. After the UHBPA_RF high-frequency amplifier is removed, the resistance value of 75_RFFE2_SDATA_BB Bus get back to normal.

Clean the solder pad, and then install a new UHBPA_RF chip. Use Fluke digital multimeter to measure the iPhone motherboard again, all data measured are normal.

Assemble the iPhone 6S, insert the SIM card, press the power button to turn it on. After the iPhone 6S is turned on, the signal is normal, and all functions tested are normal.

Hope these ways can solve your iPhone no SIM issue. If you have more effective methods, please comment below. Thanks for reading.