Your Xiaomi Redmi 9 is no longer on, the screen is black, and the indicators are not responsive to charging? This problem is familiar to many owners of budget Xiaomi smartphones, especially after 1-2 years of active use. The reasons can range from a trivial battery discharge to serious hardware breakdowns. But don’t rush to carry the phone to the service center – in 70% of cases, the device can be “reanimated” yourself.
In this article, we will discuss all the possible reasons why Redmi is a good person. 9 (including Redmi modifications 9A/9C/9T) You'll learn how to tell a software failure from a hardware malfunction, when to try to restore the phone at home, and when to consult a specialist. Particular attention will be paid to the method of forced reboot through the test mode (EDL), It works even when the screen is completely dead.
1. Checking for obvious causes: charging and mechanical damage
Before you start complex manipulations, eliminate the basic problems. Start by examining the phone:
- 🔋 Check the charger and cable. connect the Redmi 9 to another power supply (preferably the original one on the phone). 10W) cable USB Type-C. Sometimes the problem lies in a damaged cord or weak current from the "left" adapter.
- 🔌 Clean the charging connector. Dust, dirt, or contact oxidation can block the power supply. Use a toothpick or compressed air, but not metal objects!
- 💥 Look for signs of physical damage. Cracks on the body, dents or moisture under the screen (condensation) indicate a fall or ingestion of fluid. In such cases, self-repair can exacerbate the problem.
If the indicator does not light up after connecting to charging, try to leave the phone on charging for at least 30 minutes - perhaps the battery is completely discharged and takes time to collect the minimum charge. OTG-power-bank).
⚠️ Note: Do not use "fast" charging on the 18W+ For a discharged Redmi 9, it can damage the power controller. Start with a standard 5 unit–10W.
2. Forced reboot: Hard Reset and button combinations
If the phone doesn't respond to the power button, but you're sure the battery is charged, try a forced reboot. There are two working methods on the Redmi 9:
- Classic Hard Reset: Press the power button + increase volume for 10-15 seconds until the Mi logo appears. If the screen remains black, try 2-3 times.
- Alternative method (for “hang” devices): Press the power button + volume reduction for 20 seconds. This can work if the phone is getting stuck during the boot stage of the OS.
If you have a Recovery menu after you restart, select Reboot with volume buttons and confirm with the power button. If the menu doesn't appear, move on to the next step.
☑️ Checking before Hard Reset
⚠️ Warning: Don't confuse Hard Reset with Wipe Data! Forced Reboot doesn't delete data, and Recovery resets wipes everything from internal memory.
3. Diagnostics via PC: Fastboot and Qualcomm EDL Mode
If the phone doesn't show signs of life, but the PC can see it, you can try to restore the firmware through special modes, and you will need a computer with Xiaomi drivers installed and Mi Flash Tool or Fastboot programs.
Step 1. Check the connection in Fastboot:
- Connect the Redmi 9 to your PC via USB.
- Press the power button + volume reduction for 5-7 seconds.
- If a rabbit in a hat appears on the screen (Fastboot Mode), the phone is ready for firmware.
Step 2: Recovery through EDL (Emergency Mode):
If Fastboot doesn’t work, try EDL (Emergency Download Mode) mode.
1. Disconnect the phone from the PC.
2. Close the contacts test point on the motherboard (disassembly is required).
For the Redmi 9, it's two pins next to the battery (see photo).
3. Connect the USB- cable to a PC – the device will be defined as Qualcomm HS-USB QDLoader 9008.In EDL mode, you can flash your phone through the Mi Flash Tool, but it takes skill. Without experience, it's better to go to the service - the wrong firmware can finally "kill" the device.
Where to find a test point on Redmi 9?
| Regime. | How to activate | Signs of work | What can I do? |
|---|---|---|---|
| Fastboot | Power + Volume reduction | Screen with a hare in its hat | Swipe through Mi Flash, unlock the bootloader |
| Recovery | Power + Volume Increase | Blue menu with Reboot, Wipe Data items | Reset settings, clear cache |
| EDL | Close Test Point + Connect USB | PC sees Qualcomm 9008 | Restore the firmware with a "brick" |
4. Battery problems: how to check and what to do
The battery is one of the Redmi 9's most vulnerable areas, and over time, it loses capacity, it swells up, it refuses to hold charge, and it's a bad battery.
- 🔋 The phone is switched on only from charging, but switches off when disconnected.
- 🔥 The body swelled or there was a characteristic smell.
- ⚡ The swelling is going to stop (it will stop).
If you suspect a battery, try the following:
- Check the voltage. With a multimeter, measure the voltage at the battery contacts. Normal is 3.7-4.2V. If below 3.0V, the battery needs to be replaced.
- Rock the battery. Connect the phone to charge for 1-2 hours, then turn it off and try to turn it on. Repeat 2-3 times.
- Replace the battery. Redmi 9 will suit the battery LB41 or LB42 (5020 mAh). Cost - from 800 rubles, replacement in the service - 500-1000 rubles.
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If the battery is swelling, don't try to puncture it or heat it! This can cause fire, carefully remove the battery in gloves and dispose of it at a special reception point.
In rare cases, the problem lies not in the battery itself, but in the power controller (chip). PMIC). Its replacement requires soldering and costs 1500-3000 rubles. To diagnose a faulty controller can only be in the service using the help of the DC Power Supply.
5. Software failures: firmware, bootloop and "brick"
If the phone vibrates or flashes the screen, but it doesn't load beyond the Mi logo, it's the firmware that's to blame. It's called bootloop, which is a cyclical reboot.
- 📱 Failed update MIUI.
- 🔧 Installation of custom firmware or root rights.
- 🛠️ Damage to system files (for example, after resetting settings).
How to fix bootloop:
- Reset cache via Recovery: In the Recovery menu, select Wipe & Reset → Wipe Cache.This won't delete data, but it can eliminate the hangover.
- Download the official firmware for Redmi 9 (model M2004J19C) from en.miui.com, then select Clean All (erase data!) or Save User Data (save files) via the Mi Flash Tool.
- Restore via EDL (if the Fastboot doesn't work).
If the phone has turned into a brick (it doesn’t respond to anything, even charging), the reasons may be more serious:
- 🔥 Damage to eMMC memory (storage chip).
- 🔧 Wrong firmware through SP Flash Tool (for Mediatek).
- 💾 Failure in the boot or recovery section.
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If the phone is not detected in either the Fastboot or the EDL, and the battery is in good working order, there is a 90% chance of a hardware problem (motherboard, memory), self-repair in this case is almost impossible.
6. Hardware malfunctions: when without service can not do
If all software methods have been tried and Redmi 9 still doesn't work, the problem is probably hardware.
| Malfunction | Signs. | Cost of repair (₽) | Can I fix it myself? |
|---|---|---|---|
| Damage to the motherboard | The phone does not respond to charging, no indication | 2000–5000 | ❌ Diagnostics and rations required |
| Burnt Power Controller (PMIC) | Charging is jerky or does not go at all | 1500–3000 | ❌ You need micro-salvage skills. |
| Damage to the screen plume | The screen is black, but the phone vibrates / sounds are there | 1000–2000 | ⚠️ Perhaps with care. |
| Power button malfunction | The phone is turned on spontaneously or does not respond to pressing | 800–1500 | ✅ Can be replaced by yourself |
How to choose a service center:
- 🔍 Look for reviews about a particular masters (not the center in general).
- 💰 Compare prices: too cheap repairs can mean using used parts.
- 📄 Require a guarantee for work (minimum 3 months).
- 🔧 Check if they use original parts or analogues (Redmi 9 is often repaired with parts from Redmi). 9A, which is not always correct).
⚠️ Warning: If the phone has been in water, don't turn it on or plug it into charging! Immediately remove the battery and dry the board in rice or silica gel for 24 to 48 hours. Turning on the wet device shorts the circuit.
7 Prevention: How to avoid problems in the future
To make the Redmi 9 last longer without crashes, follow the following simple rules:
- 🔋 Don't discharge the phone to zero. The optimal charge range is 20 to 80 percent.
- 🔥 Avoid overheating.Do not leave your phone in the sun or near heat sources (e.g., on a car torpedo).
- 📱 Update the firmware, but not through OTA, It's manually (downloading the full package from the official website), which reduces the risk of failure.
- 💾 Don't install custom firmware without experience.Redmi 9 on a Mediatek Helio processor G80 sensitive to unofficial assemblies.
- 🛡️ Use a cover and protective glass. Mechanical damage is one of the main causes of the "death" of budget smartphones.
Regularly (every 3-6 months) reset your cache through Recovery, which clears temporary files that may cause you to freeze:
1. Turn off the phone.
2. Press the power + increase the volume.
3. From the Recovery menu, select Wipe & Reset → Wipe Cache.
4. Confirm and restart the phone.💡
If your phone starts to slow down or spontaneously reboot, back up your data via Mi PC Suite or Google Account, which will save your photos and contacts in case of a sudden crash.