How to Fix iPhone 7 Plus No Service with Warning Sign | Chip Level Repair

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We have received an “No Service “iPhone 7 Plus from our customer who claimed the baseband couldn’t be verified after system restoration. When we power on and test, we found that the iPhone is “No Service “with a warning sign in the status bar, and therefore we confirmed it’s caused by baseband failure. There are a lot of possibilities to create a baseband problem, in our previous article we have shared a baseband repair case. In this article, we will share more about baseband repair techniques, hope you enjoy our sharing.

Step 1 Function Test

Power on and test the iPhone 7 Plus, the iPhone 7 Plus shows “No Service” with a warning sign (exclamation mark) in the status bar, we therefore confirmed it’s the baseband problem.

Step 2 Diagnosis

Use the multimeter to measure the diode resistance of the baseband circuits. The C5604_RF is measured short circuit. C5604_RF short circuit is mainly caused by defect RF IC XCVR1_RF, a very common problem in iPhone 7 Plus.

Step 3 Troubleshooting & Repairing

Carefully check the motherboard, capacitors have no burnt nor water damage. Take off the RF IC XCVR1_RF and remeasure, the diode resistance showed normal, so it was the defect RF IC caused the baseband problem.

Replace a new good RF IC XCVR1_RF and solder well.

Step 4 Reassemble and Test

Reassemble and restore the iPhone, power on, everything backs to normal, repair completed.

Please refer to below detailed video:

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Tools and Materials Used in This Video:

Solder flux

Hot air gun

Microscope

Multimeter

Tweezers

PCB cleaner

Cleanroom wipes

Desoldering braid/solder wick

Motherboard fixture

Knife blade

Screwdriver

Spudger

iSlack suction pump/opening pliers

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