Xiaomi Redmi Note 9 Pro is constantly rebooting: what to do

When the Xiaomi Redmi Note 9 Pro is constantly rebooted, it can unbalance even the most relaxed user. Instead of the usual desktop, you see an endless Mi logo or a short-term turn on of the screen and then quench. This failure, often called a “cyclical reboot” or bootloop, can be caused by both a software conflict and a serious hardware malfunction.

Before you take your device to the service center, you should try to diagnose the problem yourself, most of the time it's a memory overload, an incorrect system update, or a malfunction in a particular application, and understanding the nature of the failure is the first step to restoring your gadget to health.

In this article, we’ll look at all the possible reasons why the Redmi Note 9 Pro is going into a reboot and provide step-by-step troubleshooting instructions, from simple methods like Safe Mode to complex flashing procedures, you’ll find a solution for your case.

Diagnostics of hardware buttons and external factors

The most common but often ignored reason for a cyclic reboot is sticking the power button. Mechanical locking of the key in the pressed position makes the system think that the user is endlessly trying to turn off or restart the device. In the Redmi Note 9 Pro model, the button is located on the side, and moisture or fine debris is not uncommon under it.

Take a close look at the side of your smartphone. If you're wearing a phone in a case, take it off and check if it's pressing a button. Sometimes the dense silicone shifts and puts constant pressure on the Power mechanism. Try pressing the button several times quickly and clearly to "swift" the mechanism if it's stuck.

Also, it is necessary to exclude the influence of external accessories. Connected non-original charging cable or damaged power supply can give unstable voltage, which is perceived by the system as a signal to restart.

⚠️ Warning: If after removing the case and cleaning the button the problem persists, but the phone still turns on, install the application to check the status of the buttons to eliminate the software "glitch" of the sensor.

Checking for external factors is a base without which further action may be useless. Make sure the screen does not have cracks in the plume area, as damage to the matrix can also cause short circuits.

Problems with charger and battery

The unstable power system is the second most common reason why the Xiaomi Redmi Note 9 Pro can go into a perpetual reboot. If the voltage drops below a critical level at the time of peak load on the processor, the phone emergency shuts down and immediately tries to turn on again, which creates the illusion of a software failure.

First of all, replace the cable and power supply with the ones that are known to be working. Cheap charges from the nearest stall often do not hold the declared power required for fast charging 33W, which this model supports.

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Try charging your phone off for 2-3 hours, and if it doesn’t go into reboot during that time, the problem could be a power controller or a deep battery drain.

The state of the battery itself is also key: Lithium polymer batteries degrade over time, and if your device is a few years old, the capacity could have dropped so much that the phone can't start the operating system.

• 🔋 Check if the battery is swelling (the back cover may move slightly away from the body).
• ⚡ Use the original cable USB-C power-loss.
• 🌡️ Pay attention to temperature: overheating above 45 degrees causes emergency protection.

If the phone reboots at the time of charging or when a certain percentage of charge (for example, 15% or 80%), this is a sure sign of battery wear or malfunction of the power controller on the board.

Downloading to Safe Mode to Find the culprit

If the hardware is good, it's probably software that's the problem. A conflict of a newly installed application or a cache error can cause a cyclical reboot. To check for that, you need to run the Redmi Note 9 Pro in Safe Mode, and only system applications are loaded in this state.

The login procedure may vary depending on the version of MIUI. Usually you have to wait for the logo to appear, then press the volume button, and if the phone successfully boots and stops rebooting, then the third-party application is to blame.

In Safe Mode, you'll see a corresponding icon in the corner of the screen, and now your task is to analyze what you've been installing or updating lately, often caused by "optimizers," "memory cleaners," or heavy games that are incompatible with the current firmware version.

⚠️ Warning: Do not delete system applications in safe mode, even if they seem suspicious.

If removing the latest apps didn’t work, try clearing the cache of all programs. Go to settings, find the Apps section, and sequentially clear the cache from resource-intensive programs such as the browser, social networks, and instant messengers.

Removing problematic software often brings the phone back to life, but if the cyclical reboot continues in safe mode, it means that the system files are damaged or there is a hardware malfunction.

Cache cleanup and reset via Recovery Mode

When normal booting is not possible, Recovery mode comes to the rescue. It is a special diagnostic interface built into the phone's memory that allows you to perform system maintenance without starting the main OS. Access to it on the Redmi Note 9 Pro is a combination of buttons when the phone is turned off.

To enter the menu, press the Volume Up and Power buttons simultaneously. Hold them until the Mi logo appears, then release the power button, continuing to keep the volume, and you will see a multi-point menu that is controlled by volume buttons and selected by the power button.

First, try clearing the cache, select Wipe Cache (if available in your version of the recovery) or the same, which will delete temporary files that may have been corrupted, and this operation will not affect your personal data, photos and contacts.

If cleaning the cache didn’t help and the Xiaomi Redmi Note 9 Pro reboots again, you’ll have to go to radical measures – a full reset of data (Wipe Data), which will return the phone to factory settings.

Before you run Wipe Data, make sure you remember the password from your Google account and Mi Account if the phone was tied. After the reset, the system will require authorization to prove ownership.

Lack of internal memory as a cause of failure

One of the hidden reasons for the instability is the critical lack of free space in internal storage. Android operating system and MIUI shell require a reserve of space to create temporary files and swap partition. If more than 95-98% of memory is occupied, the phone can go into an endless reboot.

In this case, even entering safe mode can be difficult. If you manage to see the desktop for even a few seconds, immediately delete heavy files: videos, WhatsApp archives or Telegram, which often take up gigabytes.

Sometimes the system prevents you from deleting files through the standard interface because of freezes, and in this situation, connecting your phone to your computer in file transfer mode can help (MTP), If you can make a decision, try to clear Download folders through the PC Explorer. DCIM.

It's also worth checking the system folder for bug logs. Debugging files can grow to huge sizes, taking up all available space. Deleting them manually or through special cleaning tools can save the situation without completely resetting.

If the phone doesn’t turn on entirely because of overcrowded memory, only a reset via Recovery (described above) will help, resulting in data loss but bringing the device back to life.

Hardware malfunctions: processor dump and memory

Unfortunately, the Redmi Note 9 Pro (especially the Snapdragon 720G versions) has a known hardware problem, often referred to as a processor or memory dump, due to a malware of the contacts under the chip as a result of overheating or mechanical shocks.

The symptoms of this malfunction are specific: the phone can suddenly turn off and no longer turn on, either hang on the Mi logo, or reboot cyclically. Sometimes it helps to lightly press the back cover in the area of the camera or processor — if at that moment the phone “comes alive”, the problem is precisely the contact of the chip.

⚠️ Warning: Warming up your phone with a hair dryer or battery is a temporary and dangerous measure that can permanently damage your screen array or other components. Use this method only as a last resort to save data.

To fix this problem, you need to have a professional repair in the service center, and the wizard needs to perform the rebolling procedure of the processor or memory, and you can't do it yourself without a soldering station and experience.

It is also worth checking the display and battery plumes. The departure of the plume from the board often causes a short circuit, which the system perceives as a critical error and initiates a reboot to protect the components.

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If the phone falls into reboot with a light tap on the body, it is 100% a sign of poor contact between internal components or the processor.

Flashing the device through Fastboot

If the software failure is deep and resetting through Recovery does not help, the last software method is complete flashing. For the Xiaomi Redmi Note 9 Pro, this can be done through Fastboot mode using a computer and the official Mi Flash Tool utility.

To enter this mode, press the Volume Down and Power buttons. The screen will show an image of a hare repairing an android and the words Fastboot. Connect the phone to your PC with the original cable.

You will need to download the current firmware for your model (it is important not to confuse the global version with the Chinese or Indian) and unpack it. In the Mi Flash Tool, select Clean All mode, which will completely delete all data and install a clean system.

adb reboot bootloader


fastboot devices

These commands on the command line will help check if your computer sees your device in bootloader mode. If the fastboot device command issues a serial number, the connection is there and you can start the firmware.

The flashing process takes 5 to 15 minutes, and it's important not to interrupt the power of the computer or shut down the cable at this time, and once it's done, the phone will automatically restart with the clean system.