Overheating Xiaomi Redmi Note 9? 12 proven ways to cool your smartphone

Xiaomi Redmi Note 9

In this article, we will discuss all possible causes of heating Redmi Note 9 (including Note 9 Pro and Note models). 9S) And we'll give you step-by-step cooling instructions, from basic methods to technical solutions, and you'll learn which apps are to blame for heating, how to clean your phone from dust, and when to go to the service.

Important: If your Redmi Note 9 is heated to 50°C and above (can be checked in the engineering menu or through applications such as: AIDA64), This is a critical indicator, and long-term operation at these temperatures accelerates battery degradation and can damage the chipset.

Why Xiaomi Redmi Note 9 is overheating: 5 main reasons

Overheating of a smartphone is rarely accidental, almost always the result of one or more problems.

• 🔥 Intensive load: games (Genshin Impact, PUBG Mobile, videotaping in 4K Long video calls are forced to process MediaTek Helio G85 (or Snapdragon 720G In the Pro-version, work at the limit.
• 🔋 Battery problems: A worn-out battery (capacity below 80% of nominal value) or a faulty charging controller can cause local overheating in the lower part of the body.
• 📱 Background processes: viruses, mining bots, or “heavy” applications (such as Facebook or TikTok) that are not optimized for the use of the software. MIUI.
• 🌡️ External factors: direct sunlight, high ambient temperature (above 30)°C) or use of a heat-locking cover.
• 🛠️ Hardware malfunctions: dried thermopaste, dust-clogged cooling system or damaged charging connector.

On the Redmi Note 9, overheating often manifests itself unevenly: the upper part (near the camera) heats up during games, and the lower part (near the port) is hot. USB-C) — It's related to the location of the chipset and the battery.

⚠️ Warning: If the phone is heated even in standby mode (without active use) and discharges quickly, this may indicate a software failure or hardware malfunction.

How to quickly cool Xiaomi Redmi Note 9: emergency methods

If your phone is already hot and you need to reduce the temperature, use these methods:

• ❄️ Turn off your phone for 10 to 15 minutes, and even when it's off, it'll cool down faster than when it's on standby.
• 📴 Remove the case - many silicone or plastic cases reduce heat transfer, especially for models with a metal body.
• 💨 Point a fan at your phone (but not cold air from the air conditioner – a sharp temperature drop can cause condensation inside the case!).
• 🔌 Turn off charging if the phone is warming up while recharging. Use the original Xiaomi power supply (up to 18W for the Note 9 and 33W for the Pro version).

Don't put a hot phone in the fridge or freezer! This can cause condensation inside the case and damage to the motherboard. Also avoid liquid-filled cooling pads - they often leak.

Critical temperature for Redmi Note 9 – 55°C. When it reaches the device, it will automatically shut down to avoid damage. If it does, don't turn it on immediately - let it cool to 30-35.°C.

Software Ways to Reduce Heat

If the phone is warming for no apparent reason, the problem may be in the software.

1. Close the background applications

V MIUI Many programs continue to work in the background, even if you've folded them, to close them:

1. Open Recent Apps (swipe up with a delay).
2. Swipe left/right on each application or click "Close everything".
3. For full closure, go to Settings → Annexes → Managing applications and forcibly stopping suspicious processes.

2. disable unnecessary functions

• 📶 5G/4G: If the network signal is weak, the phone spends a lot of energy searching for it. 3G In Settings → SIM-maps and mobile networks.
• 📍 Geolocation: turn off GPS Apps that do not need it (Settings) → Confidentiality → Permits → Geolocation).
• 🔄 Auto Update: Ban background app updates in Play Market → Settings → Auto-update of applications.

3. Update firmware

Old versions. MIUI (Below 12.5) were power management bugs that overheated:

1. Go to Settings → About the phone → System update.
2. Download the latest version (for Redmi Note 9 current — MIUI 14 based on Android 12).
3. After the update, reboot.

4. Reset the settings to factory

If nothing helps, do a hard reset (but save the data first!):

1. Go to Settings → About the phone → Reset settings.
2. Choose to erase all data.
3. After reset, do not restore the backup – install the applications again to avoid transferring the “garbage”.

⚠️ Warning: If the phone is still warming after reset, the problem is likely hardware (thermopaste, battery or motherboard), in which case only the service center will help.

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To check which application heats the processor the most, install CPU Monitor AIDA64 They're going to show you the core loading and the temperature in real time.

Hardware cooling methods: what you can do yourself

If the software methods don't work, it's time to look under the hood. Some procedures can be done at home, but beware - wrong actions can take away the guarantee.

1. Dust cleanup

Dust clogs the speaker and microphone grilles, impairing heat transfer, to clean the phone.

• 🎵 Use a soft brush (for example, for drawing) or a compressed air balloon (sold in electronics stores).
• 🚫 Do not blow with your mouth – moisture from the breath can get inside the body.
• 🔍 Pay special attention to the area around USB-C port-and-speaker.

2. Thermopaste replacement

The thermopaste on the Redmi Note 9 processor dries over time, which worsens the heat transfer.

1. Take the phone apart (you need a plastic mediator and a cross screwdriver).
2. Remove the metal screen covering the motherboard.
3. Remove the old paste with alcohol and apply a new one (such as Arctic) MX-4).
4. Collect your phone, making sure all the plumes are connected correctly.

Checking the battery

A worn-out battery not only discharges quickly, but also warms up.

• Using ##4636## (see the Battery Information menu for Wear Level).
• Or in the AccuBattery app (showing the actual capacity and temperature of the battery).

If the capacity fell below 3000 mAh (at a nominal of 5020 mAh), it is time to change the battery.

Refrigeration accessories for Xiaomi Redmi Note 9: what really works

If you're actively using your phone for games or video, you should consider cooling it down, and consider the most effective accessories.

• 🎮 Gaming coolers with fans: for example, Black Shark FunCooler Pro or Razer Phone Cooler. USB-C And reduce the temperature by 5-10.°C.
• 🧊 Passive radiators: metal plates that are glued to the back cover (such as the Arctic Cooling Plate) are a cheap solution, but the efficiency is lower than that of active coolers.
• 🔋 External cooled batteries: Some powerbanks (such as Xiaomi Mi Power Bank Pro) have built-in fans that cool both the phone and the battery itself.
• 📱 Heat sink cases, like Spigen Thin Fit with aluminum inserts, not as efficient as coolers, but better than standard silicone cases.

When choosing a cooler, pay attention to:

• Compatible with Redmi Note 9 (some models are designed only for flagships).
• Noise level (cheap cooler fans often buzz loudly).
• Additional ports USB-C (So you can charge your phone during cooling).

Cons of accessories:

• Active coolers discharge the battery faster (consume 1-3 W).
• Passive radiators add weight and thickness to the phone.
• Some covers degrade the signal GPS and NFC.

⚠️ Attention: Cheap liquid cooling pads often leak, and if liquid gets inside the phone, it will short-circuit and cause the motherboard to fail.

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Active coolers (with fans) are more efficient than passive ones, but require connection to the air. USB-C The best option for gamers is Black Shark FunCooler Pro.

When to contact the service: signs of serious malfunctions

Not all overheating problems can be solved by yourself. Contact Xiaomi Service Center if:

• Phone heats up to 50°C and higher, even in standby mode.
• There was a bloating of the body or a gap between the screen and the frame (a sign of a bloated battery).
• The smartphone spontaneously turns off at temperatures below 50°C.
• Artifacts (strips, flickering) appear on the screen when heated.
• Charging is very slow (more than 4 hours from 0 to 100%) or the phone does not hold a charge.

Average cost of repair in the service:

Before the service visit:

1. Make a backup of the data (Settings → Additional → Backup).
2. Write down the phone's IMEI (type *#06#).
3. Check whether the warranty is maintained after repair (in official services Xiaomi – yes).

Preventing overheating: How to avoid problems in the future

To prevent the Redmi Note 9 from warming up, follow these guidelines:

• 🔋 Use the original charger (18W for the Note 9 and 33W for the Pro). Cheap Chinese power supplies often lack overheating protection.
• 🌞 Avoid direct sunlight. Don't leave your phone on a car torpedo or windowsill in summer.
• 🎮 Limit it. FPS C graphics settings for most games (e.g, PUBG Mobile can set a limit of 30 or 60 frames per second – this will reduce the load on the processor.
• 📱 Update apps. Developers often release patches that optimize power consumption.
• 🛌 Do not use your phone while charging for high-intensity tasks (games, video) and this increases your temperature by 10 to 15.°C.

It is also useful to perform calibration of the battery once every 2-3 months:

1. Discharge the phone to 0% and let it stand off for 3-4 hours.
2. Charge up to 100% without interruptions (use the original cable).
3. Repeat the cycle 2-3 times.

This will help to reset the power controller errors and improve the accuracy of the charge display.

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If you play on your phone often, install the Game Booster app (built-in) MIUI). It automatically optimizes performance and temperature during play.

FAQ: Frequent questions about overheating Xiaomi Redmi Note 9