How to check the battery on Xiaomi Redmi 4X: from the code *#*#4636#*#** to disassembly

Why the Redmi 4X battery goes down in an hour: when to check the battery

Xiaomi Redmi 4X (codenamed santoni) was released in 2017 with a lithium-polymer battery with a capacity of 4100 mAh. After 3-4 years of active use, even the highest-quality battery loses up to 30-40% of its original capacity. But how to understand that the problem is in the battery, and not in the firmware or background of running applications?

Typical symptoms of a dying battery on the Redmi 4X: sudden shutdowns with 20–30% charge, discharge in 1-2 hours in standby mode, overheating during charging or playing, bloating (as seen from the "open" back cover). If any of these signs are familiar, it's time to diagnose the battery. In this article, we will discuss 5 working methods for checking the battery on the Redmi 4X, including hidden engineering menus and a physical examination.

Important: Redmi 4X does not support fast charging, so if the phone has started charging longer than 3-4 hours - this is another alarm signal. But before you run to the service, try the methods from this manual. 80% of battery problems are solved by software diagnostics or battery replacement (the cost of a new one is from 500 to 1200 rubles).

Method 1: Check through the engineering menu (#4636##)

The fastest way to get data about the battery is to use a hidden engineering menu, which is available on all Xiaomi smartphones, including the Redmi 4X, without root rights.

1. Open the Phone app.
2. Enter the combination: ##4636## (enter stars as is).
3. In the menu that appears, select Battery Information.

In this section, pay attention to the following parameters:

• 🔋 Level of charge (level) – current percentage in numbers (may differ from the status bar icon).
• 🔌 Power source – Must be a battery (if connected to a charge, will be usb or ac).
• 📊 Health is the perfect Good, if Unknown, Dead or Overheat, the battery needs to be replaced.
• ⚡ Voltage – The Norm for Redmi 4X at 100% charge: 4.35-4.4 V. If below 3.7 V - critical discharge.
• 🔥 Temperature (optimal 25–40)°C. Above 45°C - overheating.

⚠️ Warning: If you have Overheat at Health, immediately disconnect your phone from charging and let it cool.Continued use in this condition can cause battery bloating and damage to the motherboard.

Check the battery temperature (should be ≤40°C)

Turn off charging and restart the phone

Remove the cover - it can block the heat sink

Try another cable/charger-->

Method 2: Application-based diagnostics (AccuBattery, CPU-Z)

Standard MIUI tools provide minimal battery information, you'll need third-party applications for deep diagnostics, and the best options for Redmi 4X are:

1. AccuBattery (free, no root)

• 📱 Shows the real capacity of the battery (compared to the factory 4100 mAh).
• 📉 Builds discharge and charge graphs, reveals "gluttonous" applications.
• ⚡ Estimates the charging speed (norm for Redmi) 4X: 1–1.5% per minute).
• 🔋 Predicts battery wear in percentage (critically above 50%).

How to use:

1. Install AccuBattery from Google Play.
2. Charge your phone to 100% and wait until it is completely discharged (before it is turned off).
3. In Health, look at the design capacity, and if it's below 2,500 mAh, the battery is worn out.

2. CPU-Z (free, no root)

This app gives the technical data about the battery:

1. Open the Battery tab.
2. Look at Level (charge level), Voltage (voltage), Temperature (temperature).
3. Compare Technology – it should be Li-polymer.

⚠️ Attention: If in CPU-Z In the Health field, you have Unknown, and the phone turns off at 30 to 40 percent charge, which is a sign of a faulty power controller, and you may need to repair the board, not replace the battery.

💡

If the AccuBattery shows a capacity below 3000 mAh, but the phone is stable, calibrate the battery: fully discharge before turning off, then charge to 100% without interruption. Repeat 2-3 times.

Method 3: Visual inspection and mechanical inspection

If software methods have not revealed problems, but the phone is behaving strangely (for example, rebooting itself or not holding a charge), it is time to examine the battery physically.

• 🔧 Plastic spatula (mediator) or suction cup.
• ⚡ Torx screwdriver T5 (rear-cover).
• 🧤 Gloves (battery should not be taken with bare hands!).

Step-by-step:

1. Turn off the phone and remove the tray for SIM-map.
2. Heat the back cover with a hair dryer (temperature 60-70 ° C) for 1-2 minutes - this will soften the glue.
3. Put the lid on the shoulder blade at the headphone jack and carefully remove it.
4. Unscrew 8 Torx T5 screws around the perimeter.
5. Disconnect the battery plume (it is under the black tape).
6. Examine the battery for the subject: 🔍 Bloating (the battery body must be smooth). 💧 Electrolyte stains (white or green spots). 🔥 Scorched areas (dark spots on the board near).

⚠️ If the battery is swelling (even a little), you can not:

1. Puncture it with a needle will lead to a fire.
2. Continue to use - the risk of short circuit.
3. Throw in the garbage - hand over for disposal at the points of reception of batteries.

Method 4: Checking through ADB (for advanced users)

If you want the most accurate data on the battery, you can use ADB (Android Debug Bridge), which requires a computer and minimal command line knowledge.

Instructions:

1. Install. ADB-PC drivers.
2. Turn on USB Debugging on your phone: Go to Settings → About Phone. Tap 7 times on MIUI to activate Developer Mode. Go back to Settings → Additional → For Developers and turn on USB Debugging.

Redmi 4X

adb shell dumpsys battery

In the answer, find the following parameters:

• Level is the current charge in percentage.
• Voltage: Voltage in microvolts (divided by 1000 to get volts).
• Temperature is a temperature in tenths of a degree (for example, 345 = 34.5°C).
• health – condition (2 = good, 3 = overheating, 7 = unknown).

Example of output for a serviceable battery:

level: 85


voltage: 4120 (4.12 V)




temperature: 325 (32.5°C)




health: 2 (Good)

💡

If ADB has a health setting of 3 (Overheat) or 4 (Dead) and the phone is cold, the problem is with the charging controller, not the battery.

Method 5: Test under load (stress test)

Sometimes the battery behaves normally in a simple, but instantly sits down when you load (games, video, navigator).

1. Charge the phone to 100%.
2. Turn off Wi-Fi, mobile data and sync.
3. Launch it. 3D- play, PUBG Mobile or Genshin Impact on maximum graphics settings.
4. Watch the discharge through AccuBattery or a standard battery monitor.

Normal performance for the Redmi 4X:

• 🎮 Discharge in play: 8-12% per hour.
• 📺 Discharge when watching video (YouTube, 1080p): 5-8% per hour.
• 📱 Standby Discharge (screen off): 0.5–1% per hour.

If the discharge occurs 2-3 times faster, the cause may be:

• 🔋 Heavy-worn battery (capacity) <2000 mic).
• 🛠️ Faulty power controller (requires diagnosis in the service).
• 🤖 Background activity of viruses or curved optimized applications.

💡

Before the test, cool the phone to room temperature under load, and overheating distorts the results: at 50°C, the battery loses up to 20% of its capacity temporarily.

When to change the battery: checklist for Redmi 4X

Replacement of the battery is required if:

The phone turns off at 20-30% charge

Capacity by AccuBattery <2500 mAh

Bloating of the body (rear cover "opened")

Voltage at 100% charge <4.0 V

Battery temperature >50°C without load-->

Cost of replacing the battery with the Redmi 4X (2026):

• 🔧 Original battery (Xiaomi): 1000-1500 rubles + work 500–1000 rubles.
• 🔋 Analogue (quality, for example, Remax): 500-800 rubles + job.
• ⚠️ Cheap no-name: 300-500 rubles, but the risk of swelling after 3-6 months.

Where to replace:

• 🏠 Xiaomi’s official service is a 6-month warranty, but more expensive.
• 🔧 Local service is cheaper, but check reviews.
• 🛠️ Independently – only if you have experience disassembling smartphones.

Frequent questions about the Redmi 4X battery