How to check your own smartphone or Xiaomi equipment: the full guide

Have you just bought a used Xiaomi Redmi Note 12 or noticed the strange behavior of your Mi 11 Ultra after a fall?Maybe you are planning to purchase a Mi Band 8 smartwatch and want to make sure it is not a fake.In any case, checking Xiaomi equipment before buying or after an incident is not a whim, but a necessity. Even new devices from official stores sometimes have hidden defects, not to mention goods from hand or after repair.

This article is not about scratching the body, but about deep diagnostics, from testing hardware components to testing software integrity. You will learn how to detect replacement components, hidden damage after falling or getting moisture, and how to distinguish the original Xiaomi equipment from fake, POCO, Mi, tablets (Pad 6), smartwatches (Watch 2 Pro) and even routers (Mi Router).

1. External inspection: what reveals a fake or hidden damage

Start with visual analysis -- it takes 5 minutes, but it can detect up to 60 percent of the problems. Take the device in your hand and turn on a bright light (better use a flashlight).

• 🔍 Logo and inscriptions: On the original Xiaomi devices, the logo on the back is clear, without blurring the edges. On fakes, there are often typos in the model name (for example, "Redmmi" instead of "Redmi").
• 📏 Gaps and assembly: Check the joints of the case - on the original smartphones, the gaps between the screen and the frame are minimal (less than 0.3 mm). If the case "plays" when pressed, this is a sign of poor build or replacement of the rear cover.
• 🎨 Paint quality: On fakes, paint often flakes off at corners or has an uneven hue. Xiaomi's original devices are painted by anodizing (for metal cases) or use a matte coating without shine.
• 🔌 Connectors and buttons: Insert SIM-card - in the original slots it is fixed with a characteristic click. The buttons on and volume should be pressed with the same force, without backlash.

Pay special attention to the following repairs:

• 🛠️ Autopsy marks: On the back cover, look for screwdriver scratches near the screws (even if they are hidden under stickers). On the original devices, the screws have a special coating that is damaged when unscrewed.
• 🔧 Uneven screws: If the screws are different lengths or one is missing, it is 100% a sign of disassembly.
• 📱 Battery sticker: The original batteries have a holographic sticker with a serial number, and if it's not there or it's damaged, the battery is replaced.

⚠️ Attention: On Xiaomi 2023 devices+ year of release (for example, Xiaomi) 13T) It's a laser engraving of the serial number on the body, and if it's erased or painted, you're looking at a fake or a device after unqualified repair.

Screen check: how to identify broken pixels and sensor issues

The screen is the most vulnerable element in any gadget, and even microcracks that are invisible to the naked eye can cause the display to fail.

A test for broken pixels

Go to MonitorTests or use the Screen Test app from Google Play. Consistently display single-color screensavers (black, red, green, blue, white).

• ⚫ Black screen: Broken pixels will be visible as colored dots (red, green, blue).
• ⚪ White screen: Check the uniformity of the backlight - dark spots indicate the detachment of the matrix.
• 🔴🟢🔵 Color screens: Look for stripes or gradient transitions that shouldn't be.

Sensor and multi-touch check

To test the sensor layer:

1. Open the Touch Screen Test (or similar) app.
2. Swipe your finger over the entire area of the screen - the line should be smooth, without tears.
3. Touch the screen at 5-10 points at the same time (multi-touch). All dots must be recorded.

Critical signs of screen failure:

• 📵 "Dead Zones: Screen areas that do not respond to touch.
• 🌀 ghost touches – the screen reacts without your influence.
• 🌈 Rainbow divorces when tilting the device - a sign of damage to the polarization layer.

Diagnosis of the battery: how to find out the real wear of the battery

The battery is the second most important component after the screen, and even if the smartphone is on and running, it doesn't mean that the battery is OK. Hidden wear and tear can cause the device to suddenly shut down or the battery to blow up. Here's how to check its condition:

Method 1: Through the phone menu (for MIUI)

Go to Settings. → Battery → Battery status. This is the display:

• 📊 Wear rate (percentage) If the value exceeds 20%, it is time to change the battery.
• 🔋 Real capacity (e.g. 4,500 mAh out of 5,000 mAh) A difference of more than 15% is critical.
• 🔄 Number of charging cycles: Lithium polymer batteries have a lifespan of 500 to 800 cycles.

Method 2: Engineering menu (for all Android)

Enter the dialer code:

##4636##

Go to the Battery Information tab. Notice the parameters:

• Health – Must be Good (if “Unknown” or “Dead” – battery is faulty).
• Voltage is the normal value at 100% charge: 4.2-4.4 V.
• Temperature above 40°C in normal use indicates degradation.

Method 3: Visual inspection

If you have access to the battery (for example, when changing the screen), check:

• 🔍 Bloating: Battery should be flat. Even a slight bulge is a reason to replace it.
• 📏 Sizes: Compare to the original battery (e.g. for Redmi Note) 10 Pro capacity 5020 MAC, sizes 158×75×3.5 mm).
• 🏷️ Marking: Original battery must have: Serial number (coincides with number on box), Xiaomi holographic sticker, Production date (no older than 1-2 years).

⚠️ Attention: If the battery is swelling, you can't puncture or heat it. Lithium polymer batteries can ignite if damaged. Take the device to a recycling service center.

Check the level of wear in the settings

Start the test of the engineering menu (#4636##)

Check the battery for swelling (if available)

Compare the real capacity with the passport

Ensure that there are no spontaneous reboots when 30-40% charge

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4.Camera testing: how to detect module substitution or damage

Cameras in Xiaomi smartphones are often the victims of unskilled repairs, such as when a fall only the external module can be replaced and the internal lenses remain damaged.

Step 1: Checking the hardware

Turn on the camera and do the following:

• 📸 Focus: Point the camera at text from 10-15 cm. Autofocus should work in 1-2 seconds. If the image remains blurry, the module or train is damaged.
• 🔦 Stabilization: Take video in motion (for example, walking around the room). If the picture "jumps" - the gyroscope or software stabilization is defective.
• 🌓 Aperture: In Manual Mode (Pro Mode) change the aperture value (f/1.8 → f/16). If the exposure does not change, the diaphragm mechanism is broken (relevant to Mi). 11 Ultra, Xiaomi 13 Pro).

Step 2: Test all modules

Xiaomi smartphones often use multiple cameras. Check each one:

Step 3: Checking for Module Substitution

Fake cameras may look like original cameras, but they're of worse quality to detect the substitution:

1. Install the Camera app MX Manual Camera.
2. Take a photo in format RAW (treatmentless).
3. Upload the picture to the DPReview website and compare it to the reference photos of your model.

Signs of a fake module:

• 📉 Low light quality drop (heavy noise, loss of parts).
• 🔍 Lack of laser or phase autofocus (checked in Pro Mode).
• 📸 Megapixel mismatch (for example, instead of 108 MP, the camera outputs 12 MP).

💡

If the camera gives an error "Did not connect" - try to clear the cache of the Camera application in the settings. If this does not help, the problem is in the plume or module (disassembly required).

5 Performance Check: How to Identify Trottling and Hardware Limitations

Even if a smartphone turns on and on, it doesn't mean it's using all the potential of hardware. A common problem with used devices is trottling. Here's how to spot it:

Test 1: Benchmark Applications

Install AnTuTu Benchmark or Geekbench 6 and run the full test. Compare the results with the references for your model (can be found on the GSMArena website).

• 📊 If the result is lower by 20%+ — Possible trottling or chipset wear.
• 🔥 If the device overheats above 60°C during the test - thermopaste replacement is required.

Test 2: Manual testing

Follow the following steps to check for stability:

1. Run Genshin Impact or Call of Duty Mobile at maximum settings.
2. Play for 15-20 minutes while watching FPS (Use GameBench).
3. If FPS Falls from 60 to 30–40 – this is a sign of trottling.

Test 3: Checking the Limitations MIUI

Xiaomi sometimes artificially restricts performance on used devices.

1. Install the Throttling Test CPU from Google Play.
2. Run the test for 10-15 minutes.
3. If the graph shows a drop in the CPU frequency below 50% of the maximum, the restrictions are included.

How to remove restrictions (if any):

• 🔧 Reset the settings to factory (Settings) → The phone. → Resetting settings).
• 📱 Swipe the device through the Mi Flash Tool (requires unlocking the bootloader).
• 🔥 Replace the heat paste (relevant to the POCO F3, Redmi K40 and other "hot" models).

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If the smartphone dramatically loses performance when heated to 45-50°C is normal (overheating protection), but if trottling occurs at 35-40.°C, this is a sign of chipset wear or cooling problems.

6. Diagnostics of network and communication modules: Wi-Fi, Bluetooth, GPS, 5G

Communication problems are one of the most common malfunctions after falls or moisture, and even if your smartphone catches the network, it doesn't mean that all the modules are working correctly. Here's how to check them individually:

Check Wi-Fi and Bluetooth

Perform the following tests:

• 📶 Wi-Fi speed: Connect to a 5GHz network and run a speed test on Speedtest.
• 🔄 Connection stability: Move around the room – the connection should not break.
• 🎧 Bluetooth: Connect your headphones and check: Sound quality (no wheezing or cliffs); video latency (should be minimal); connection range (at least 10 meters in line of sight).

Checking the mobile network (4G/5G)

Use the Network Cell Info Lite app to analyze:

• 📡 Signal level: Must not be lower -100 dBm (the closer the 0, better).
• 🔄 Switching between cells: When moving, the smartphone should smoothly transition between towers, without breaks.
• 📶 Internet speed: On 4G — at least 30 Mbps, at 5G — 100 Mbps.

Critical malfunctions of communication modules:

• 🚫 Lack of networking at work SIM-map - damaged module or antenna.
• 🔄 Constant switching between 3G/4G — modem-problem.
• 📡 Low signal strength (below) -110 dBm) with good coating - damage to the antenna path.

Verification GPS

For testing. GPS:

1. Install. GPS Test or Google Maps.
2. Enable high-precision location (Settings) → Security and location → Regime. → High precision).
3. Go out into the open space and wait for the satellites to be fixed (at least 10).
4. Check the accuracy - the error should be within 5-10 meters.

⚠️ Attention: If GPS No satellites or coordinates jumping 100+ It's a sign of damage to the antenna or module, and 80 percent of the time, it's just a replacement motherboard.

7.Authentication Check: How to distinguish Xiaomi original from fake

Fake Xiaomi devices may look almost like the original, but have the worst features and often fail.

Step 1: Checking IMEI and serial number

Each Xiaomi device has unique identifiers to verify:

1. Type *#06# and it will be displayed. IMEI.
2. Compare it to the number on the box and under the battery (if you have access).
3. Check it out. IMEI IMEI.info – the model must match.

Step 2: Check through the official Xiaomi service

Go to Mi Verify and enter the serial number (you can find it in Settings). → The system will show you the phone:

• 📅 Activation date (if the used device, it must match the words of the seller).
• 🏷️ Warranty status (if warranty is valid – original device).
• 📦 Model of the device (must match the inscription on the box).

Step 3: Checking the firmware and hardware

Fake devices often run on the left-hand firmware to detect this:

• 📱 Go to Settings. → The phone. → Version. MIUI.
• 🔍 Compare the official version for your model on the website MIUI Downloads.
• 🛠️ Install. AIDA64 and check: CPU model (must match official specifications) RAM (fakes often have less than that) RAM). Screen resolution (for example, Redmi Note) 11 Pro it should be. 1080×2400).

Signs of a fake device:

• 📱 The settings display a non-existent model (e.g., "Redmi") X9").
• 🔋 Battery discharges in 2-3 hours (original Xiaomi keep charge at least 6-8 hours).
• 📸 The camera takes pictures of worse quality than in reviews.
• 🔊 Speakers wheez or no stereo sound (in the original models two speakers).

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If the serial number on the Xiaomi website is not found, and the seller claims that the device is original - before you 100% fake or device after unofficial repair with the replacement of the motherboard.

8.A check after moisture hits: what to do and how to diagnose damage

If your Xiaomi falls in water or has been in the rain, even after drying, there may be hidden damage.

Step 1: Visual inspection for corrosion

Disassemble the device (if you have skills) or inspect the available connectors:

• 🔌 Charging port: Look for green or white plaque is corrosion.
• 🔊 Speakers and microphones: Water leaves white stains on grids.
• 📱 SIM tray: If there is moisture inside - the smartphone is not sealed.

Step 2: Checking moisture indicators

Xiaomi smartphones have hidden moisture indicators to find.

• 🔍 Remove the back cover (or shine a flashlight through the glass).
• 🔴 Look for red or pink markers (normally white).
• 📍 Location of indicators: Near the battery, under the sim tray, near the charging connector.

Step 3: Testing after drying

Even if the device is turned on, check:

• 📶 Network: Moisture infestation often disables the antenna module.
• 🔊 Sound: Microphones and speakers may wheez or not work.
• 📸 Camera: Moisture leads to fogging of the lenses (pictured will be blurred spots).
• 🔋 Charging: If the phone does not take charge or warms up, the power controller is damaged.

⚠️ Note: If the moisture indicators are triggered, Xiaomi’s warranty is automatically removed even if the device is working".

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If the smartphone hits salt water (sea), wash it with distilled water before drying - salt accelerates corrosion 5-10 times.

FAQ: Frequent questions about Xiaomi vetting