Buying a smartphone in the secondary market or from dubious sellers always carries the risk of encountering a poor-quality replica or device with hidden defects. Xiaomi Redmi 4X, despite its age, is still in demand as a reliable budget device, which makes it a frequent target for fraudsters selling fakes. It is important to understand that the appearance of the case does not guarantee the identity of the “stuffing”, so comprehensive diagnosis before buying or immediately after receiving a parcel is a mandatory procedure.
Verifying this gadget requires a consistent approach, including software analysis, unique identifiers, and a thorough examination of physical components. Ignoring at least one of the steps can lead to the purchase of a brick or machine with replaced, unoriginal parts. In this article, we will discuss in detail all available verification methods that will help you avoid financial losses and ensure that the device is working.
Analysis of the appearance and quality of the assembly of the body
The first thing that catches your eye when you look at the device is the materials and the quality of their processing. The original Redmi 4X is made of metal with high-quality sandblasting, while replicas often have a plastic case covered with metal paint, or low-quality metal with burrs. Carefully examine the joints between the screen and the frame: the gaps should be minimal and uniform throughout the perimeter, and the backlash of the case is completely excluded.
Pay special attention to markings on the back cover and tray SIM-The original device is clearly engraving, deep and easy to read, whereas for fakes it may be blurred or missing. Also check the location and movement of the control buttons: they should have a clear, elastic click, and not fall or creak when pressed.
- 🔍 Check the uniformity of the gaps around the perimeter of the screen – they should not walk when pressed.
- 🔍 Estimate the weight of the device: the original weighs about 138 grams, fakes are often lighter or heavier due to other materials.
- 🔍 Consider the Mi logo on the back at an angle: the original it does not erase and has clear boundaries.
⚠️ Warning: If you smell cheap plastic or glue when disassembling (or even without it), this is a sure sign of a low-quality replica collected in artisanal conditions.
The build quality directly affects the longevity of the gadget, so any creaking or wobbling of the case should alert the potential buyer. Even if the software looks convincing, the physical mismatch with the brand standards overrides all other benefits.
Verification of IMEI and serial number through system codes
The most reliable way to identify a phone is to match unique identifiers. Every legal smartphone has a unique IMEI code that is prescribed in the factory. To quickly check the dial screen, you need to enter the combination *#06#. Once you enter the command, a window with the main data of the device will appear on the display.
Compare the numbers displayed on the screen with those shown on the box and on the sticker under the back cover (if it is removable) or in the tray. SIM-The complete coincidence of all the numbers is the first sign of originality. IMEI In software, so just checking the numbers may not be enough.
You can also use code ##4636##, which opens a hidden engineering menu, and here in the Phone Information section, you can see more details about the network and device status, and if you don't enter the codes, or if the menu looks primitive and different from the standard MIUI, that's a reason to question the authenticity of the firmware.
- 📱 Make sure that IMEI It consists of 15 digits and contains no letters or symbols.
- 📱 Check if the status is displayed SIM-Maps in the engineering menu after installing the SIM.
- 📱 Note the baseband version: it should not be listed as "Unknown».
The absence of a second number in the drossym version may be the norm, but requires clarification of the modification of the device.
Diagnostics through the official CIT menu and engineering test
Xiaomi smartphones have a special diagnostic mode known as CIT (Customer Integration Test), which you need to go to the settings menu, select About phone and quickly click on the kernel version several times, or enter the code ##6484##. This menu allows you to test each component of the device separately.
Go through all the test items: check the vibrator, the multi-touch screen, the proximity and light sensors, microphones and speakers. In Touch, swipe the entire surface, all the cells should be green without any omissions, which is critical for detecting the sensor's dead zones.
| Component | What we check. | Normal result |
|---|
| Touch (screen) | Sensor response | All cells are stained, no lines are broken. |
| Receiver (Dynamic) | Sound on the bell | Pure sound without wheezing and coding |
| Vibrator (Vibro) | Mechanical vibration | Uniform vibration throughout the body |
| Backlight (backlight) | Screen brightness | Smooth change in brightness, no flickering |
What to do if the CIT test does not start?
If you enter the code ##6484## Nothing happens, maybe a custom firmware or a modified system application is installed, so try downloading the official Mi Test app or reflashing the device to the stock version. MIUI. On some global versions, the entrance may be hidden, then the code will help ##64663##.> Don't ignore checking the sensors, especially the accelerometer and the gyroscope. CIT There are tests to calibrate these components, and if the phone doesn't respond to turns or the game doesn't see the tilts of the device, it means that the sensor is faulty or not connected, which often happens after unskilled repairs. Verification through Mi Account and official website The most authoritative source of information about the device is the server of the manufacturer (S/N) and activation code. Then go to the official Xiaomi authentication portal. By entering the serial number in the appropriate field on the site, you will receive information about the date of production and activation status of the device. If the system says that the device is not found, or the activation date is very different from the date of your purchase (for example, the phone is “activated” a year ago), this is an alarm signal. Perhaps you are trying to sell the restored (refurbished) device as a new one. It is also useful to link the device to your Mi Account. In the About menu, try to click on the logo of the MIUI version several times to open the extended menu, or simply log into your account through the settings without the official configurations, as the Chinese authors can synchronize with the service. ⚠️ Note: If the system requires to be unlocked through the account SMS Or it indicates that the device is locked by a previous owner (Mi Cloud Lock), do not buy one, and it is almost impossible to circumvent this protection legally. Checking the site also allows you to know whether the device is listed as stolen or lost, although this feature does not work equally well in all regions. Chinese replica makers often use old or cheap processors, masking their names in the system. 4X, The original model is based on the Snapdragon 435 chipset, while fakes may have MediaTek or older versions of Snapdragon. For detailed diagnosis, install a specialized application, for example, CPU-Z or AIDA64. These utilities will show the real name of the processor, its frequency, number of cores and type of RAM. 3 GB RAM, a the program shows 1 GB 2 GB, so the memory was software "bloated" (flash the file build.prop). 🚀 Compare the CPU frequency: the original Snapdragon 435 squatting 1.4 GHz. 🚀 Check the screen resolution: for Redmi 4X standard is 1280×720 (HD), Not full. HD. 🚀 Pay attention to the number of nuclei: they should be 8, But in standby mode, some of these can be turned off to save energy. IPS-screen. If the color is inverted (becomes negative) or fades greatly, it may be a cheap one. TN-The battery and battery charging system are one of the most worn out components, and the condition of the used devices plays a key role. 4X battery-powered 4100 In the engineering test menu CIT via code ##6485## You can see the parameters. MB_06 (degree of wear) and MF_05 (number of recharge cycles: if the number of cycles exceeds 300-500, The battery is more than the battery. 20-25%, The actual autonomy will be significantly lower than the stated one, and it is also worth checking the charging speed: the original device with Quick Charge support. 3.0 It should charge fast enough, while fakes can heat up and charge for hours.Visually inspect the Micro-USB charging connector. It should sit tight, without backlashes. If the cable falls out at the slightest movement or the device stops seeing charging when position changes, the connector requires soldering, which is a sign of active use or repair. ⚠️ Attention: A bloated battery is a direct security threat, and if the back of the phone is swollen or the screen is swelled by pressure from the inside, it is forbidden to operate the device. Remember that the software can be adjusted, so the best test battery is real use: turn on the video at maximum brightness and record the time of operation. A sharp drop in charge from 40% to 5% in a few minutes indicates a deep degradation of the cells. Frequently asked questions (FAQ) Can I re-fake the Redmi fake? 4X No, it's impossible. The hardware stuffing of fakes (processor, memory, screen) is radically different from the original. MIUI It's going to stop the device from turning on because the drivers won't match the hardware. MIUI Global, but the site says no device is found, and it's likely that the device has a modified firmware that manually inscribes the original serial number, and the actual serial number may be in another device or it may be generated by accident. This is a common sign of a Chinese man embroidered. How do you check if the bootloader is unlocked? When you turn on the phone on the screensaver MIUI (logo on white background) must appear the image of the lock with the words "Unlocked" (if it is unlocked. You can also check the status on the Developer menu, "Mi Unlock status." Is it normal for the Redmi 4X to warm up when charging? A little heat around the top of the case (where the processor is) is acceptable. However, if the phone is hot to hold in your hand, or the area near the charging connector is warming up, this indicates a power controller malfunction or battery degradation.