When you recycle or refurbish an iPhone cracked LCD screen, you need to check whether iPhone LCD display is good or bad. But how do you test a broken LCD screen? Many friends think the LCD is good, but when they sell the iPhone cracked screen in the market, the professional people may tell them that the LCD screen has many defects. It means a loss. So, we need to know how to test an iPhone LCD well.

There are two ways of testing the LCD screens. One way is using a tester; the other way is using an used iPhone to test. A tester is fast and simple, but it is not good enough to see the touchscreen fully. Using an iPhone to test the LCD screen is slow, but it is comprehensive.

Now I will share you our experience of how to use an iPhone to test a LCD screen. These steps are for Apple iPhone LCDs. But you can test Samsung, Sony or other brands phones according the same ways. You can see the picture about “iPhone + extended flex cable” as below:

We can sell you these flex cables, they are usually 3 to 4 USD depending on what models.

Now we start testing steps:

1)Check the screen apperance and connect the LCD screen to iPhone

When you start to test a LCD display, you need check to the cracked LCD apperance first. If the LCD or flex cable is broken very badly such as lack of some corner, you can judge that this LCD has no value. If you could decide it, please connect the LCD screen to an iPhone, turn on the LCD. If the screen could not be turned on when the connection of cables are good, it is considered as a  “black screen” and it is considered to has no value or little value.

2) test the LCD touch function

Press and hold an app icon and move from the ouside LCD to inside. Please see the video.

3) check the LCD if there are color spots, pressure spots

You need three background pictures, black, white and gray. And in the background you can see the details if the LCD display is defective.

below pictures are the examples which have defects:

4) test if the flex cable connecting is not good.

Push and pull the LCD slightly and watch the changing in the LCD. If the LCD display have changed, the connecting flex cable may not be good.

OK. Now you can confirm the LCD screen is good, if you could not see any defects after the steps above. Is it very easy? Hope this post can help you.