Released on September 19, 2014, this 4.7" screen iPhone is the smaller version of the iPhone 6 Plus.

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How to check u2 before replace

hi the team

can you help me please

I have an iphone 6 with problem u2

How should i do u2 test before changing it

Be sure it is damaged

I have power supply

Thinks the team

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There is no magic bullet when testing for a Tristar (U2) issue. Tristar is responsible for communicating with any device plugged into the Lightning port. Here are some suggestions to help you determine if U2 is the problem:

  • Plug in a USB ammeter. It should show drawn current if the phone is truly charging.
  • Does the phone get recognized by an iTunes enabled computer?
  • Does the phone show the charging symbol but the percentage doesn't change or the Ammeter shows no current draw?

Here is a good blog post on U2 symptoms.

N'hésite pas à continuer de poser des questions, c'est de cette façon qu'on apprend!

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thinks bro minho good job

I am very grateful to you


I can take this video into account MINHO


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When I started in mother board repair, we would wonder a lot about this exact question.

- OK so everything before seems to be working properly.

- We have the right symptoms.

- Yet we are not confident enough in our micro-soldering and micro-BGA skills, so we really want to be sure before attempting to replace it.

- Here's the spoiler: there is no real fool proof method to rule it out until you.. replace it. This is the single most efficient way to trouble shoot it. If you are good at it, it should take 5 minutes to remove, clean pads, install new one. 20-25 minutes from lifting screen to reassembling last screw.

- Bonus point: Tristar chips (which you call U2, but should really call Tristar if you want to sound professional) are sort of consumable parts of an iPhone board. They "deteriorate" as you use them specially from power spikes, fake chargers, fake cables, poor quality car chargers, lightning accessories. They are cheap too. So if you suspect them, it is always good to replace them. You can only do good for the device and the trouble shooting process.

- Common Tristar symptoms: not recognized by computer; not charging; charging slowly; booting from charged battery but unable to charge a flat battery.

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thinks bro RANY

I am very grateful to you



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There are components near U2 IC that tells the voltage they have when phone is powered on, meaning test them with battery and phone powered up. You can see in the schematics the value, 5v and 1.8. if the result value is lower than that then its time to change the U2.



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You're right my friend I saw her on ZWX

But I got better answer by you three


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Mike Plouvin will be eternally grateful.
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