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Repair iPhone 7/7P Signal Part

Today, we are going to talk about iPhone 7 7 Plus no signal issues. Actually, if your iPhone 7/7P shows no signal, then you can't make the phone calls or sent messages. Unless your iPhone 7/7P is in WiFi coverage, otherwise the iPhone won't be able to contact with others. Here are three types of no signal issues and related solutions.


1. iPhone 7/7P has no signal at all, infinite search.

Get into IOS, go to Settings>- General>- About to check whether there is the IMEI.

If the IMEI is not displayed on this iPhone, then you need connect iPhone to DC power supply to check iPhone boot current, and then determine if it has a large current issue. If there is a phenomenon of leakage, then you can fix it with leakage methods; if the current is normal, then you can directly replace the baseband power without test, and then re-install the iPhone baseband CPU.

If IMEI is displayed on the iPhone normally, then set up the time (WiFi Automatic settings available), enter the Dial-up interface, press *#06# to see if the IMEI can be displayed. If IMEI can't be displayed, then you need to use hot air gun and tweezers to replace Power Amplifier IC-QPOET_RF, and replace baseband power BBPMU_RF, re-install the baseband CPU--BB_FR, replace LBPA_RF, replace MHBDSM_RF.

2. iPhone 7/7P has no signal at all, try different SIM card


Press *#06# and the IMEI can be displayed normally, and then you can try insert different SIM card to check. If you insert any SIM card, it still shows no signal, and then you can check the antenna under the Trinocular Stereo Microscope, and then replace it, replace MF IC and Power Amplifier IC-QPOET_RF.

3. Some damaged IC will cause different SIM card has no signal

It is noteworthy that if system under the hardware abnormal case, then the 4G function will be auto close. If there is no 4G or even you fixed the hardware, but still no 4G, you can erase all the data and then restore settings.

The following IC damage will cause the iPhone 7/7P no signal(you can check it on WUXINJI Dongle):

XCVR1_RF (CDMA and WCDMA receive)
MHBDSM_RF
GSMPA_RF2G Amplifier
MBHBPA_RF Amplifier

More professional cell phone repair skills, please visit on www.vipfixphone.com

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