Xiaomi Redmi 9A is one of the most popular budget smartphones, but many users are faced with the question: why does their device not support fast charging out of the box?In fact, you can enable accelerated charging on this model, but you need to consider several key points – from the correct charger to hidden settings MIUI.
In this article, we’ll explore how to speed up the Redmi 9A’s charging speed without risking battery damage, how to check its current charging speed, and what to do if it fails to charge faster, and uncover myths about fast charging in budget smartphones and give practical tips for extending battery life.
Why doesn’t Redmi 9A support fast charging by default?
Xiaomi Redmi 9A is equipped with a battery capacity of 5000 mAh, but, unlike the more expensive models of the Redmi Note or POCO series, it does not have built-in support for fast charging technologies such as Quick Charge or Fast Charge+. the manufacturer has limited the maximum charging power at 10 W (5V/2A) is a standard indicator for most budget devices.
But that doesn't mean that you can't speed it up, because the limitation is software-based: the smartphone just doesn't ask the charger for more power, even if it can provide it, but there are ways to get around that limitation, partially or completely, depending on the hardware used.
⚠️ Warning: Exceeding the recommended charging power can shorten battery life.If you plan to use a smartphone longer than 2 years, it's best to stick to the standard 10W.
The main reasons for the lack of fast charging:
- 🔋 Budget power controller - in Redmi 9A installed the simplest charging control chip that does not support accelerated charging protocols.
- 📱 Limitations MIUI — Firmware artificially reduces power consumption to protect the battery.
- ⚡ Complete charger - the power supply unit coming in the kit gives everything 5V/1And (5 W) which is twice as slow as possible.
What Chargers Are Suitable for Accelerated Charging?
To increase the charging speed of the Redmi 9A, the first thing you need to find the right charger. Even if the smartphone does not support Quick Charge 3.0 or Power Delivery, some power units can deliver more power through the standard USB BC1.2 protocol (up to 7.5 W) or DCP (up to 10 W).
Here are the charges worth considering:
- 🔌 Standard. 5V/2And (10 Watts is the safest option that does not require additional settings, any charger from Xiaomi, Samsung or Apple (for example, a unit from an iPhone or Redmi Note) will do).
- ⚡ 9V/2And (18 Wh/supported QC 2.0/3.0 — Some users report that such charges (for example, from the POCO X3 or Redmi Note 9 Pro) allow charging speeds to be achieved 12–14 W, but only when manually activated in the engineering menu.
- 🔋 Power supplies with Power Delivery (PD) — It could work, but the Redmi could. 9A It does not support this protocol, so the speed will remain at 10W.
Cable also plays a role. For maximum speed, use the original Xiaomi cable or a certified USB-Type C with data support (not all cheap cables can withstand current above 1A).
| Type of charger | Max Power for Redmi 9A | Do you need a setup? | Risk to the battery |
|---|---|---|---|
| Complete (5B/1A) | 5 watts | No. | Minimum |
| Standard 5B/2A | 10 Watts. | No. | Low. |
| Quick Charge 2.0/3.0 (9B/2A) | 12-14 W** | Yes (engineering menu) | Medium. |
| Power Delivery (5V/3A or 9V/2A) | 10 Watts. | No. | Low. |
* - The actual speed depends on the MIUI version and battery status.
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If you’re using a charger from another device, check its power using the Ampere app (available on Google Play) to show the actual current and voltage the smartphone receives.
How to check the current charging speed?
Before you try to speed up charging, you should know how fast your Redmi 9A is charging right now.
- Through the system menu: Connect your smartphone to charge. Go to Settings → Battery, click on the icon. ⚡ Next to the percentage of charge – the current power will be displayed (for example, “Charging” 5V/1And»).
- With Ampere: Install Ampere from Google Play. Connect charging and open the app, and it will show current (in mA), voltage (in V) and design power (in W).
The following are the normal performances for the Redmi 9A:
- 🔋 5V/1And (5 W) - complete charge.
- ⚡ 5V/1.5–2And (7.5–10 W) - standard charge 5V/2And.
- ⚠️ 9V/1.5And (13.5 W) – only possible with manual setting (see next section).
If the app shows a current below 500 mA when charging, it means that the smartphone has switched to slow charging mode due to overheating or battery wear.
Step-by-step: how to enable fast charging through the engineering menu
The most effective way to unlock fast charging on the Redmi 9A is to activate hidden settings via the Engineering Mode, which works on most versions of MIUI, but requires caution: incorrect changes can lead to crashes.
Warning: Before starting, back up your data and make sure your battery is at least 30%.
Save important data on PC or in the cloud|Check the level of charge (minimum) 30%)|Prepare the charger 9V/2And|Install a monitoring application (Ampere)-->
Step 1 Open the Engineering Menu
Enter the following code in the Phone application:
##4636##You'll open the Test menu. Select Battery Information. Here you'll see the current charging options, but you can't change them here, you need to go deeper.
Step 2: Activate the fast charging mode
Go back to the main menu of the phone and enter a new code:
##2846579##The ProjectMenu will open, and then you'll see:
- Select Background Setting → Battery charge setting.
- Find the Fast charge or Quick charge setting and set the Enable value.
- In some versions of MIUI, you may need to enable USB high speed.
- Save the settings and restart the smartphone.
Step 3. Check the result.
After rebooting, connect your smartphone to a 9V/2A charge and check the speed through Ampere. If done correctly, the current should increase to 1.5-1.8A at 9V, which corresponds to a power of 13-16W.
⚠️ Warning: After activating fast charging, the smartphone can warm up more. 40°C, turn off the function and return to standard charging 5V/2And.
What to do if the engineering menu is not opened?
Software methods to accelerate charging without an engineering menu
If you don’t want to take risks with engineering settings, there are safer ways to increase charging speed:
- 🔄 Turn off background processes: Close all apps before charging (especially games and social media). → Annexes → Run and stop unnecessary services, it will reduce the load on the processor and reduce heating.
- ❄️ Turn on Airplane Mode: Turning off mobile and Wi-Fi reduces power consumption, allowing more power to be used to charge. Speeds can increase by 10 to 15%.
- 🔋 Use Power Saving Mode: Paradoxically, the inclusion of Power Saving Mode in Settings → The battery sometimes speeds up charging as it limits background activity.
- 📵 Charging with the screen off: If you do not use your smartphone while charging, the system automatically reduces power consumption, which speeds up the process by 5-10%.
It is also worth checking the battery status, if it is worn out (capacity below 80%), the charging speed will be artificially limited, and you can check the wear and tear using the AccuBattery app (available on Google Play).
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The safest way to speed up charging is to use a 5V/2A charger and turn off all background processes, which will give you up to 30% increase without risk to the battery.
Frequent problems and their solutions
Even after all the settings, the Redmi 9A can charge slowly, and let’s look at the typical causes and ways to fix them:
| Problem. | Possible cause | Decision |
|---|---|---|
| Charging is too slow (less than 500 mA) | Battery wear or damaged cable | Check the cable, try another power supply, and if the problem persists, replace the battery. |
| The smartphone does not recognize fast charging | Inactive setting in the engineering menu | Repeat the activation steps (see section above). |
| Charging is interrupted or not going | Overheating or contamination of the USB connector | Clean the dust connector, let the smartphone cool down. Charge at 10-35°C. |
| After the MIUI update, the charging speed fell | The new version of the firmware reset the settings | Re-activate fast charging via the engineering menu. |
If none of these methods worked, there might be a hardware problem, like a damaged power controller, and you'd better go to a service center.
Myths about fast charging on budget smartphones
There's a lot of rumors about the Redmi 9A's accelerated charging, and we'll figure out what's true and what's not.
Myth 1: “Any Quick Charge Charge will speed up charging to 18 watts”
❌ That's not true. 9A It doesn't support Quick Charge or Power Delivery at the hardware level, and the best you can do is 12 to 14 watts through manual settings, but only with certain power supplies.
Myth 2: “Fast charging ruins your battery in six months”
⚠️ Partly true, but nuanced. Today's lithium-ion batteries are designed to last 500 to 800 charge cycles. Rapid charging increases heat, which can reduce that time by 10 to 15 percent, but not by much. If you plan to use a smartphone for 1-2 years, the difference will be subtle.
Myth 3: “You need to discharge your smartphone to 0% to calibrate”
❌ Bad advice: Deep discharge (below 3%) is bad for the battery; optimal charging range is 20-80%; full cycle (0-100%) should be carried out no more than 1 time per month.
Myth 4: “Wireless charging is faster than wired charging”
❌ No, Redmi. 9A It doesn't support wireless charging at the hardware level. Even if you use an adapter, you can't go faster than 5 watts (slower than wired charging).
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If you frequently charge your smartphone overnight, set a charge limit of up to 80% through the AccuBattery app, which will extend battery life by 20-30%.