We are going to repair an iPhone 6s Plus device today, the main fault is that the phone shows no service after plugging in SIM card. Any parts get damaged? In this article, we'll show you how to diagnose and repair the problem!
Depend on preliminary judgement, there are generally 2 parts get fault for no service phenomenon: signal channel part or REFF bus. You have to distinguish carefully when testing cell phone.
After inserting SIM card, we can see the serial number when dial *#06# on dialing interface, as shown in 17-7-1, it seems that it is not the problem of the REFF bus, so we can exclude the fault caused by the bus (if the bus caused the fault, it will not enter the serial number after dialing the *#06#).
The operation option on the interface as shown in picture 17-7-2, so it means there is no problem with the receiving section. Let's check the launch section.
Take off the iPhone 6s Plus logic board and measure by Fluke digital multimeter, we found the resistance value of PP_1V0_LDO9 was only 47, which was supplied to U_WTR_RF RF IC.
Remove the U_WTR_RF RF IC to measure again, the ground resistance value returns to normal. Replace a new iPhone 6s Plus RF IC, install to have a test.
The signal finally returns to be normal state and calling function is normal too.
Summary: this failure is due to the failure of U_WTR_RF RF IC.
If you want to know more iPhone repair tutorials, please check on www.vipfixphone.com
Depend on preliminary judgement, there are generally 2 parts get fault for no service phenomenon: signal channel part or REFF bus. You have to distinguish carefully when testing cell phone.
After inserting SIM card, we can see the serial number when dial *#06# on dialing interface, as shown in 17-7-1, it seems that it is not the problem of the REFF bus, so we can exclude the fault caused by the bus (if the bus caused the fault, it will not enter the serial number after dialing the *#06#).
The operation option on the interface as shown in picture 17-7-2, so it means there is no problem with the receiving section. Let's check the launch section.
Take off the iPhone 6s Plus logic board and measure by Fluke digital multimeter, we found the resistance value of PP_1V0_LDO9 was only 47, which was supplied to U_WTR_RF RF IC.
Remove the U_WTR_RF RF IC to measure again, the ground resistance value returns to normal. Replace a new iPhone 6s Plus RF IC, install to have a test.
The signal finally returns to be normal state and calling function is normal too.
Summary: this failure is due to the failure of U_WTR_RF RF IC.
If you want to know more iPhone repair tutorials, please check on www.vipfixphone.com
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