The situation when the upper part of the smartphone screen suddenly stops responding is one of the most annoying problems for Android users. It is in this area that critical interface elements are located: the notification panel, the status bar, buttons for switching tabs in the browser and the address entry field.
The failure of the touchscreen in a specific area can be caused by either a software failure of the operating system or physical damage to the display module. Before taking the device to a service center, it is worth carrying out a number of diagnostic measures that can restore the functionality of the gadget without extra costs.
In this article we will analyze in detail the algorithms for actions in case of partial failure of the sensor layer, software calibration methods and methods for temporarily using the device until a full repair is completed.
Primary diagnostics and exclusion of external factors
First of all, it is necessary to exclude the influence of external accessories and contamination. Often, a protective glass applied with air bubbles or misalignment blocks the sensitivity of the sensor in the upper third of the display. Remove the case and protective film, then thoroughly wipe the screen with microfiber, paying special attention to the frame around the display.
Pay attention to the nature of the malfunction. If the screen responds erratically or "ghostly" to touches, this may indicate problems with capacitive layer or power controller. Try connecting the charger: if the problem disappears when working from the mains, it may be due to insufficient battery voltage or a faulty power supply.
Sometimes the cause is static electricity or overheating of the case. Let the phone cool down with it turned off for 15–20 minutes. After turning it on, check if the problem persists. If the dead zone is clearly limited by a geometric line and does not change when the screen is rotated, the probability hardware failure sharply increases.
Software methods for restoring sensitivity
If physical impact is excluded, we move on to the software part. Often, a malfunction in the sensor drivers leads to incorrect processing of touch coordinates. The first step is to force reboot your device. On most modern models Samsung or Xiaomi this is done by long-holding the power button and volume down button.
The next step is to clear the system process cache. Go to menu Settings → Applications → Show system processes. Find the application responsible for the interface (often called System UI or similar) and select the "Clear cache" option. This action will not delete your personal data, but will reset temporary files that could cause the conflict.
In some cases, updating the firmware helps or, conversely, rolling back to the previous version if the problem appeared immediately after the update. Check for updates in the section Settings → About phone → System update.
Before resetting the settings, be sure to back up your contacts and photos in Google cloud storage, as a full reset will delete all data from the internal memory.
Using the engineering menu and hardware tests
To accurately diagnose the state of the touchscreen in Android, there are built-in engineering tests. They are accessed through a special menu or by entering service codes in the Phone application. For devices on MediaTek chips, the code often works ##6484##, and for Samsung — #0#.
In the menu that opens, select "Touch" or "Sensor". You will be asked to drag your finger across the grid or draw lines. This will allow you to visually determine which areas of the sensor do not register touches. If the cells in the upper part of the grid do not light up, the diagnosis is confirmed.
Be careful when changing settings in the engineering menu. Inexperienced intervention in the calibration parameters can lead to complete inoperability of the sensor. If you are not sure of your actions, it is better to limit yourself to testing only.
Secret codes for different brands
For Huawei/Honor, use the code ##2846579##. For Sony Xperia - code ##7378423##. Remember that on some new models, access to the engineering menu may be blocked by the manufacturer.
Sensor calibration with third-party utilities
When the built-in tools do not help, you can use applications from the store Google Play. apps like "Touch Screen Repair" or "Touchscreen Calibration" offer controller retraining algorithms. The principle of their operation is to record the maximum and minimum values of the sensor capacity.
The process usually looks like this: you launch the application, follow the instructions on the screen (click on the crosses, draw lines), and then the app executes a reboot command to apply the new parameters. This may help if the crash is caused by software desync.
However, it is worth understanding the limitations of such utilities. They cannot fix a physical broken cable or damaged digitizer. If after calibration the problem returns after a few minutes, then the reason lies deeper, in the hardware of the device.
☑️ Software diagnostic algorithm
Temporary solutions for controlling a smartphone
If the upper part of the screen does not work, and you need to use the phone urgently, there are workarounds. In the accessibility settings (Settings → Accessibility), you can activate the control menu. It adds a floating button to the screen, duplicating the functions of the Back, Home and Application Menu keys.
You can also connect a USB mouse via an OTG adapter. The mouse cursor will appear on the smartphone screen, allowing you to control the interface with high precision, regardless of the state of the touchscreen. This is an ideal way to save data before going to the service.
Another option is to use a voice assistant Google Assistant. The commands “open settings”, “call a contact” or “take a screenshot” are performed without touching the screen, which partially compensates for the loss of functionality.
⚠️ Attention: Using an OTG adapter and a mouse drains the battery faster than usual. Try not to leave connected peripheral devices unattended for a long time to avoid overheating of the port.
Hardware reasons and the need for repair
If none of the software methods worked, we are talking about a physical breakdown. The most common cause of failure of the top part of the screen is the display module cable coming loose or damaged. Even a slight blow or fall can break contact in the connector.
Another option is failure of the digitizer itself (sensory layer). In modern smartphones, it is often combined with glass into a single laminated block. Replacing only glass at home is impossible without special equipment (separator and lamp).
The table below shows the main symptoms and probable causes of failure:
| Symptom | Probable cause | Solution method |
|---|---|---|
| The strip on top 2-3 cm does not work | Damage to the cable or connector | Reconnecting or replacing the cable |
| The screen reacts every once in a while | Wear of the touch layer | Replacement of the display module |
| Spots of insensitivity | Devets of the case or swelling of the battery | Replacement of the battery and checking the case |
| Complete failure after a fall | Crack in the controller chip | Replacing the display assembly |
⚠️ Attention: If you notice a swollen battery that presses on the screen from the inside, under no circumstances try to disassemble the phone yourself. This can lead to fire of the lithium element.
To replace the display, you will need to heat the case with a hairdryer to soften the glue, use suction cups and mediators for careful opening.
If the dead zone has clear boundaries and does not respond to calibration, in 95% of cases the display module needs to be replaced or the cable soldered.
Frequently asked questions (FAQ)
Can I use the phone if the top of the screen does not work?
Yes, this is possible. Use a mouse connection via OTG, activate the accessibility menu, or control the device with voice commands. However, full use, especially of the browser and instant messengers, will be difficult.
Will resetting to factory settings help if the touchscreen breaks down?
A reset will only help if the cause is purely software (driver conflict, virus, firmware failure). If the problem is physical damage to the glass or cable, resetting the settings will not restore functionality.
Why did the screen stop working at the top?
The top part of the screen is most vulnerable when falling “face down”, since the impact often falls in this area. There are also complex cables and sensors, the contact failure of which affects the operation of the adjacent area of the sensor.
How much does it cost to replace the glass if the image is OK?
The cost depends on the phone model. If only the glass is replaced (separation equipment is required), the price will be lower than replacing the entire module. However, many services only offer complete replacement of the assembled module, which is more expensive, but more reliable.
Is it dangerous to continue using a phone with broken glass?
Yes, it is dangerous. Glass shards can damage the touch layer or injure your fingers. In addition, the seal of the case is broken, and moisture or dust can get inside, which will lead to oxidation of the board and more expensive repairs.