When your loyal Xiaomi Redmi 4X suddenly stops responding to button presses, it can take anyone by surprise. Black screen, no vibration and silent speaker are just external manifestations of a problem that can be rooted in both a software failure and a hardware malfunction. Many users immediately start panicking and carrying the device into the service, but in half of cases you can reanimate the gadget yourself, having basic knowledge of the operating system Android and the interface MIUI.
Before you start to act, you need to make an initial diagnosis of the state of the battery and charger. Often the problem lies not in the smartphone itself, but in the banal discharge of the battery to a critically low level or failure of the USB cable. Try to connect the phone to another power source using the original unit and wire, and leave it for at least 20-30 minutes. If during this time the charging indicator has not caught fire, and the screen continues to shine black, then the situation requires deeper intervention.
It's important to understand that the Redmi 4X, released in 2017, is already a mature device whose component life could be exhausted. The wear of the lithium polymer battery, the oxidation of contacts or microcracks on the motherboard after falls are all real reasons for failure. If the phone makes a sound of connecting to the PC when the cable is connected, but the screen remains black, the problem with a high probability lies in the malfunction of the display module or the plume. The next steps depend on how the device behaves when you try to start up.
Software failure and system freeze
One of the most common reasons why Xiaomi Redmi 4X doesn’t turn on is a critical operating system failure. The processor can get stuck in a faulty code execution cycle, which causes the device to stop responding to any user commands. Visually, it looks like a complete shutdown, even though the phone is actually in a deep sleep or freeze state. To fix this problem, there is a forced reboot that breaks the process cycle.
To perform a hard restart, you need to pinch the power button and hold it for a long time - from 10 to 20 seconds. In some cases, a combination of the buttons Volume up + Power or Volume down + Power is required. If the device is working, you will feel a short vibration and see the Mi logo. This action is safe for your data and does not lead to its deletion, as it simulates the physical extraction of the battery.
If the phone is turned on after a forced reboot, but is unstable, it is worth checking the last installed applications. Conflicting software could cause the crash of system processes. It is also recommended to clear the system cache through the Recovery menu, which will be discussed below. Frequent freezes may indicate overflow of internal memory or damage to system files after a failed update.
Problems with charging and battery
When the Redmi 4X refuses to turn on, the first thing to do is to eliminate power problems. The battery is an expendable, and over time its capacity drops and internal resistance increases. If the phone is several years old, the battery could simply "die" and stop holding or taking charge. Visually determining the status of the battery is difficult, but an indirect sign can be a quick discharge before the final shutdown.
Carefully inspect the Micro-USB charging connector. Clothing pockets often accumulate pile and dust that are tightly sealed in the port, preventing the cable from entering the end and ensuring contact. Carefully, using a wooden toothpick or plastic blade, clean the connector. Metal items are best avoided so as not to close the contacts. Also check the cable itself for clogs and damage to the insulation.
⚠️ Warning: If the charger starts to heat up a lot in the lower part of the case (where the battery is located), immediately turn it off! this is a sign of a short circuit inside the battery or power controller, which can cause a fire.
In the case of a deep discharge, the charge indicator may not light up immediately. Leave the phone charging for at least an hour, even if the screen is black. Sometimes the power controller takes time to raise the voltage at the battery terminals to a level sufficient to start the system. If after an hour of reaction does not occur, try to "swing" the battery with short-term connections to charge.
Diagnostics through Recovery and Fastboot mode
If a normal download is not possible, it is worth checking the availability of Xiaomi's service modes. Recovery mode allows you to reset or flash, and Fastboot is used for low-level recovery. Recovery can be accessed by holding the Volume up + Power buttons before vibration occurs. Fastboot usually leads the combination Volume down + Power.
If the phone responds to these combinations and displays the corresponding menus (a black screen with text or a picture of a hare in a repair cap), then the main components of the board - the processor and memory - are most likely alive. This narrows the search for the problem to software or a display. In the Recovery menu, navigation is carried out by volume buttons, and the choice is made by the power button.
☑️ Actions in the Recovery menu
However, if the phone doesn't respond to any of the button combinations, remaining completely black, it's an alarm bell. It may be that the on button is dead or the button plume has collapsed. In rare cases, a software bootloop (cyclic reboot) prevents you from entering the menu, and the phone constantly twitches, showing the logo, in which case only the flashing through the computer helps.
Hardware and payment breakdowns
When software methods are powerless, you have to consider hardware reasons. Xiaomi Redmi 4X is equipped with a Snapdragon 435 processor, which, although reliable, is sensitive to overheating and shocks. A common problem is the collapse of the CPU contacts or memory chips due to thermal cycling (heating and cooling), which leads to the fact that the phone can turn on, but not boot, or show no signs of life at all.
Another culprit is the power controller, which distributes electricity to all the nodes of the smartphone. If it fails, the phone can show signs of life (vibration, sound), but the screen will remain black, or the device will constantly reboot. Diagnostics of the controller requires a multimeter and the ability to read electrical circuits.
The oxidation of the board after moisture is a classic cause of electronic death. Even if the phone fell into the water a week ago and seemed to work, the corrosion processes could get to important circuits, visually manifested as a white or green plaque on the board, which can be seen when you remove the back cover.
Hidden signs of hardware breakdown
Table of symptoms and probable causes
For ease of diagnosis, we have compiled a table that will help you compare the behavior of your Redmi 4X with the most likely cause of malfunction, remember that only a specialist can make an accurate diagnosis after opening the device.
| Symptoms. | Probable cause | Difficulty of repair |
|---|---|---|
| The indicator is on, the screen is black. | Display or plume malfunction | Medium (module replacement) |
| Vibration is there, no logo. | Software failure or memory damage | High (flashing/ soldering) |
| Phone warms up on charging | CZ in a battery or controller | High (replacement of components) |
| Cyclical reboot | System file or power button | Low/Mediocre |
| Total lack of response | Deep discharge or chain break | Depends on the cliff. |
Firmware recovery methods
If you've managed to enter Recovery mode, you can try to reset to factory settings. Select Wipe Data, then Wipe All Data, and confirm the action. Attention: this will delete all your photos, contacts, and apps. If the software was the problem, the phone should work as new.
A more complex but effective method is to flash through your computer using the Xiaomi Flash Tool, which requires you to switch to EDL (Emergency Download) mode. On Redmi 4X, this is often done by disassembling the case and closing special contacts on the board, since the bootloader can be locked, which allows you to restore even the "brick" by completely overwriting the device memory.
💡
Use only original or proven firmware from miui.com. Installing modified builds from unknown authors can finally kill the phone.
The firmware process requires stable USB-port (preferably) USB 2.0 at the back of the system unit, and a high-quality cable, and interrupting the recording process can lead to irreversible consequences. If you're not sure about yourself, you should leave this procedure to the professionals.
When a visit to the service center is required
There are a number of situations where self-repairing is not only useless, but also dangerous. If you see a bloating battery (the cover is raised), do not try to puncture it or push it hard. This is a direct threat to fire safety. Replacing the battery in such conditions requires caution and special tools.
If the phone fell from a height or water hit it, the count often goes to the clock. Oxidation spreads quickly, and simple rice drying does not help here - you need ultrasonic cleaning of the board in the service. Also, the workshop should be contacted if you suspect problems with soldering of the processor, as it requires a professional soldering hair dryer and chip skills.
⚠️ Attention: Self-opening of the Redmi body 4X It can damage the plumes or lose the warranty (if it still works.
The cost of repairs should be correlated with the residual cost of the device itself. For the Redmi 4X, replacing the display or complex soldering can be prohibitively expensive, and in such cases, it is sometimes more appropriate to consider buying a more modern device, saving data from the old one if possible.