Fast charging on Xiaomi Redmi Note 8 Pro: how to turn on and speed up charging to 18 watts

Why does the Redmi Note 8 Pro not always charge fast?

Owners of Xiaomi Redmi Note 8 Pro often face a paradoxical situation: the smartphone supports fast charging technology Quick Charge 3.0 (18 W), but in reality charges from the standard power supply 2-3 times slower. The reason lies not in hardware limitations, and in the software settings MIUI, which by default turn off accelerated charging “to extend the battery life”.

The manufacturer does not advertise this point: the documentation for the device indicates that the Note 8 Pro is compatible with the QC 3.0, but not a word about the need for manual activation. Moreover, even the original charging unit from the kit (the MDY-10-EP model) produces only 10 watts without additional manipulations. In this article, we will analyze all the ways to enable fast charging - from official to "hidden" methods for power users.

It’s important to understand that fast charging not only saves time, but also increases battery wear 15-20% faster when used regularly. If you plan to use a smartphone longer than 2-3 years, weigh the pros and cons before activating.

1. Compatibility Check: Which Charges Are Right for the Note 8 Pro?

Before you turn on fast charging, make sure your power supply supports the necessary protocols.The Redmi Note 8 Pro works with:

• 🔌 Quick Charge 3.0/4.0 (18 W) - best option.
• ⚡ Power Delivery (PD) (Up to 18W – partially compatible, but may require a support adapter PD 2.0.
• ❌ Standard charging 5V/2And (10 W) – will not give acceleration, even if you turn on the function in the settings.
• ⚠️ Uncertified units – can damage the battery or power controller.

How do you check your power supply? Pay attention to the labeling:

• 🔍 Inscriptions. QC 3.0, 18W, 9V/2A or 12V/1.5A — fitting.
• 🔍 Qualcomm Quick Charge logo – compatibility guarantee.
• 🔍 If it is specified 5V/2A — It's just a regular exercise.

Tip: the original unit from Xiaomi from the kit (MDY-10-EP) does not support QC 3.0! For a full fast charging you will have to buy an adapter, for example, Xiaomi Mi Charge Turbo (MDY-11-EP) or a block from Redmi K20 Pro.

Charger compatibility table

⚠️ Note: Using uncertified chargers with power above 18W (such as 30W or 65W) may overheat the Note 8 Pro power controller.

2.Official method: enable fast charging via MIUI settings

The easiest method is to activate the function in the MIUI menu, but it doesn't work on all firmware versions.

1. Open Settings → Battery and Performance.
2. Select Charging (on some versions – Charging settings).
3. Find the option "Fast Charge" (or Quick Charge) and switch the slider to the position "On".
4. Confirm the action if a warning appears about reducing the battery life.

If you don't have "Fast Charge" on the menu, your version of MIUI hides that option, so move on to the following methods.

Use an original or certified USB-C cable

Connect a compatible power supply (QC 3.0 or PD)

Close all background applications

Make sure the battery temperature is below 40°C

-->

On MIUI 12.5+ versions, the path to settings may vary: Settings → Additional → Special Features → Charging settings.

⚠️ Warning: After turning on fast charging, the smartphone can heat up to 45-50°C while charging.This is normal, but it is not recommended to use the device during accelerated charging (especially playing or shooting video).

💡

The official method only works when you connect a compatible power supply, and if the "Fast Charge" option is inactive, check the charger.

3. Hidden settings: activation via MIUI Hidden Menu (Engineer Mode)

If the standard method didn’t work, you can turn on fast charging via the engineering menu, which requires caution, as the wrong actions can disrupt the smartphone.

Instructions:

1. Open the Phone app and type the combination: ##4636## Some firmware may run ##6484## (battery testing menu).
2. In the menu that opens, select Battery Information.
3. Find the Fast Charge or Quick Charge string and click on it.
4. In the window that appears, select Enable.
5. Reboot your smartphone.

If #4636### doesn’t work, try an alternative method:

• Install the MTK Engineering Mode app (for MediaTek processors).
• Launch it, go to MTK Settings → Battery.
• Activate the Fast Charging option.

Important: on some firmware after enabling fast charging through the engineering menu, protection can work, and the smartphone will limit the current to 10 W. In this case, only resetting settings or firmware through Fastboot will help.

Table of engineering menu codes for Redmi Note 8 Pro

4. Compulsory Entry via ADB (for Advanced Users)

If previous methods didn’t work, you can try enabling fast charging via Android Debug Bridge (ADB), which requires an unlocked bootloader and installed ADB drivers on your PC.

Step-by-step:

1. Enable USB Debugging in the Developer Settings (Settings → About Phone → MIUI Version – Press 7 times, then return to Additional → For Developers).
2. Connect your smartphone to your PC and open the command line (or Terminal on Mac/Linux).
3. Enter the commands in order: adb devices (should display your device) adb shell su (if root rights are available) setprop persist.sys.qc3.enable 1 reboot

After the reboot, check the charging speed with the AccuBattery or Ampere app. If the charging current has increased to 2000-3,000 mA, the method worked.

If the commands are not executed due to lack of root rights, try an alternative method:

adb shell settings put global fast_charge 1

⚠️ Attention: Misuse of the right ADB Do not change other parameters through setprop unless you are sure of their purpose. persist.sys.qc3.enable 0 will turn off fast charging forever before resetting settings.

💡

Before using ADB, back up your data via Settings → System → Backup. This will help you recover information in the event of a crash.

5. Problems and Solutions: Why Does Fast Charging Not Work?

Even after you turn on all the settings, the Redmi Note 8 Pro can charge slowly.

🔋 Problem: charging goes to 10 watts instead of 18 watts

• 🔌 Reason: Incompatible power supply or cable is used.
• 🛠 Solution: Replace the cable with the original USB-C (For example, from the Redmi kit K20 Pro) and check the power supply for support QC 3.0.

🌡 Problem: the smartphone heats up and reduces the charging current

• 🔥 Reason: Battery temperature exceeds 45°C.
• 🛠 Solution: Remove the case while charging. Don't use your smartphone for games or videos. Place the device in a cool place (but not in the refrigerator!).

⚡ Problem: Quick Charging option is missing after update MIUI

• 🔄 Reason: Xiaomi has removed the setting in the new firmware.
• 🛠 Solution: Reverse to the previous version MIUI It's on Fastboot. ADB or engineering menu (see sections above).

📉 Problem: Charging speed drops after 80%

• 🔋 Reason: Optimized Charging Mode is Activated (Settings) → Battery → Optimizing charging).
• 🛠 Solution: Disable this option if you want 100% full charge without restrictions.

If none of these methods worked, check the battery status through the AccuBattery app. A worn-out battery (capacity below 80% of nominal) can block fast charging at the controller level.

💡

The most common cause of "failed" fast charging is a non-original cable. Even if the power supply supports QC 3.0, a cheap cable can limit current to 1-1.5A.

6. Alternative methods of accelerating charging

If you fail to turn on fast charging, you can optimize the process in other ways:

🔄 Airplane mode

Disconnection of network modules (Wi-Fi, 4G, Bluetooth reduces power consumption by 15-20% by speeding up charging. Activated through notification curtain or Settings → SIM-maps and networks → Airplane mode.

❄️ Cooling of the device

Use a cooling stand or fan (e.g. Xiaomi Yuemi USB Fan) and lowering the battery temperature by 5-10°C increases the charging current by 10-15 percent.

🔋 Background activity shutdown

Close all apps through Settings → Apps → Run and disable auto-run of unnecessary services, especially “gluttonous” messengers (Telegram, WhatsApp) and social networks.

🔄 Resetting battery settings

Sometimes a failure in the power controller results in an artificial current restriction. Reset settings through Settings → Battery → Reset battery statistics (reboot required).

For maximum effect, combine these methods. For example, charging in cooled aircraft mode can give you a speed increase of up to 30% even without a QC 3.0.

7.Myths and truths about fast charging on Redmi Note 8 Pro

There's a lot of rumors going around the Quick Charge technology.

❌ Myth: “Fast charging ruins your battery in 6 months"

✅ Truth: Modern lithium-polymer batteries are designed for 500-800 charge cycles regardless of speed. Rapid charging increases wear by 15-20%, but not critically. The main enemy of the battery is overheating and deep discharge (below 10%).

❌ Myth: The original unit from the kit supports QC 3.0"

✅ Truth: Block MDY-10-EP It only gives you 10 watts out of the box. You need a labeled adapter to charge fast enough. QC 3.0 or PD 18W.

❌ Myth: After the update MIUI fast charging is shut down forever"

✅ Truth: Settings are reset, but they can be turned on again through ADB or Hidden Menu. Exception is custom firmware, where the function can be removed at the core level.

❌ Myth: "Recharge from a laptop (USB 3.0 gives 18 watts"

✅ Truth: Ports USB PCs and laptops are limited by protocol USB BC 1.2 (max 7.5 W). Even USB 3.1 Type-C is less than 15 watts without Power Delivery support.

Bottom Line: Fast charging is safe when used correctly, but requires quality equipment and temperature control.

FAQ: Frequent questions about fast charging Redmi Note 8 Pro