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Solution: iPhone 6S Large Current Grey Fingerprint Fault

There is an iPhone 6S with a high current and gray fingerprint fault , we are going to fix today. Before repairing, we have to test it first. How to repair step by step, let's check in the article!


1. Test whether the fault is the same as what the customer said.



2. Observe under the Trinocular Stereo Microscope to check whether it has been repaired before, whether it has compression deformation, water corrosion, the most important is whether the customer's description is right.

Test result: boot current 150 mA, grey fingerprint.

- Look at the most obvious grey fingerprint according to the data.

(1) Use Fluke digital multimeter to test the resistance, voltage, we found it has short circuit phenomenon.

(2) since we found the problems, so we should eliminate them one by one.

- Test full function

(1) test full function

(2) set up the fingerprint

(3) clean the motherboard

(4) do the marks that we have dealt with.

All the problems are successfully solved now, repair is over here.

More professional cell phone repair guide check on www.vipfixphone.com

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