What to Do When the Touchscreen Stops Working?

30.01.2015

«My touch screen doesn't work» - is one of the most common problems a user of a modern smart phone, cell phone or tablet can face.
In this situation the right thing to do is to apply to a service center where qualified specialists will solve your problem.
If you still want to deal with this on your own, you will sure need our tips.

Before buying a new touch screen, find out a model of your gadget and marking of a touch screen. You should pay attention to the size and location of proximity sensors, front-facing camera, and speakers. This is especially important for devices manufactured in China. Check out our article for detailed information on how to choose a touch screen for a Chinese device

Separation of a touch screen

Before ordering a touch screen, make sure you'll be able to separate the screen by yourself. Quite often you’ll need a special equipment to separate the touch screen. When disassembling a tablet or a phone, learn the consecutive steps of disassembly, location of screws, plugs, and clips. All the necessary tools for disassembling the gadget you can find here.

Be very careful when disassembling the device, since you can accidentally damage the internal components placed close to the edges, e.g. flat flex cables, power buttons, side buttons, antenna etc.

Having disassembled the device, separate the touch screen. It is important to pay attention to the way the touch screen is attached to the display module – in some cases they can be separated, in other touch screen and display module make monolithic construction.

There are modular models, which cannot be disassembled. The touch screen can be assembled to a PCB using a bus or by a contact method. If the screen is connected with a bus, be very careful not to damage it when dissembling.

It is much simpler with a contact method (simple connection of contacts). With this type of connection you can simply separate the touch screen from the display module.

If you have a device with the touch screen glued over the entire area to the glass or display by photopolymeric glue, we recommend that you use a special separator machine.

Check out the video on how to use a separator for separating glass from the display module.

To use a separator you will need:

To re-assemble such module you will need special glue.
Our video will help you to choose the right glue for your device.

To stick the glass carefully and reliably, use a LCD module holder and UV lamp.

If you're lucky and a touch screen was separated together with a front panel but without a display, this means that it was stuck with a double-sided adhesive tape.

Such a tape can be unstuck mechanically using a thin, flat object. If the glue is stronger, you'd have to preheat glass surface using a hot air soldering station. Heat it very carefully not to damage the plastic frame.

How to choose a touch screen?

Managed to disassemble the gadget? Congrats!

Start choosing the right replacement part. As written above, the important factors when choosing a replacement part are version and marking of a touch screen.
It is also important to determine the thickness of double-sided adhesive tape. If the layer is too thick, a sensor will be bulging out of the rim too much. And vice versa, if a scotch tape is too thin, it is possible that the sensor will be stuck after assembly and won't work properly. Attention! In many devices the touch screen can’t directly contact the display or the metallic frame!

You can choose the adhesive tape in our store.

If you can't find the right thickness of adhesive tape, you can buy a thin adhesive tape and stick it in several layers until you reach necessary height.

Having dealt with everything mentioned above, you can make order in our store. If you have any questions, contact our sales manager or technical support. specialists will help you to find everything you need.

Replacement of the touch screen

Having received the ordered products, you can start repairing.

Before attaching the touch screen always check if it works!

Thus you can protect yourself from a factory defect or unnecessary disassembly in case the version of a touch screen is inappropriate. We provide warranty for all touch screens sold in our store. You can find detailed information about warranty on this page.

If a touch screen does not work from the first try, it doesn't mean that it's broken or defective! Never let touch screen contact the display! You should also check whether touch screen contacts are plugged in. You may need to clean contacts on the flat flex cable and connector with the help of an ordinary eraser, as they may oxidize.

It’s necessary to make a touch screen controller to rewrite data about a new touch screen. You need to turn on your gadget without connecting the touch screen. During the loading, the system will update the firmware of the controller. After the update OS will load. Next, you should:
take off the battery without turning off the tablet → connect the touch screen → turn on the device → touch screen firmware is updating.

This procedure is called calibration of the touch screen. It’s also used in case of an incorrect touch screen response, inverse response, sticking (hypersensitivity) or poor sensitivity of the touch screen. Sometimes the calibration needs to be done using special software which can be easily found on the Internet.

In some cases the full reflash is vital for gadget to work. Software must either be updated to the latest version or to the previous version. In situation like this it’s best for you to contact the specialists or experiment with different firmware yourself.

Sometimes just HARD RESET is enough for device to work properly. For every model this procedure is different but all of the information about these procedures is available on the Internet.

Please, be aware that all firmware updates may lead to the loss of personal information. If you decide to change your firmware, be sure to back up the contacts, photos, videos and other important data.

If the touch screen does not work, you can save the data using a computer mouse or keyboard connected via a special OTG-cable.

There are also some situations when it is necessary to do not one but several of these procedures, for example, flashing the firmware first, and then calibrating touch screen..

If you have already tried all possible methods of calibration, and the result is that the old touch screen is broken but works, and the new one does not work at all, then there is another way to get the new touch screen to work.

Sometimes the controller which is soldered directly to the flat flex cable of the screen just is not compatible with the version of your device (this is especially common with tablets from China). In this case you must desolder a suitable controller from the old touch screen and solder it to the new one. This procedure can be done only by experienced specialists. If you want to return the items, your actions must be pre-approved by the sales manager who was in charge of your order! Inaccurate soldering will void the warranty on the touch screen.

The touch screen is working? That’s excellent!

Take your time and do not take the inner protective film off the touch screen, don’t assemble the device yet. Touch screen needs to be fully tested before you do that..

If you can’t make the device to work properly, you can always return the touch screen back (if it meets the warranty requirements). For more information on how to return the items, please visit

All Spares Team is wishing you success in choosing and replacing the touch screen! We will do our best to provide you with all the necessary spare parts.

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