Xiaomi smartphone owners often face the need for deep diagnostics of devices that go beyond standard system settings. The engineering menu is a hidden software interface designed to test hardware components and calibrate sensors. On the Redmi 8 model, which runs on the basis of the MIUI shell, access to these features allows you to check the health of microphones, speakers, communication modules and screen without installing third-party software.
Many users are looking for a way to get into this section to independently identify the cause of a communication failure or a broken sensor. It is important to understand that CIT (Customer Interface Test) is a tool for specialists, but basic tests are available to everyone. Improperly changing hidden parameters can lead to unstable operation of the Redmi 8, so you should carefully study the instructions and consequences of actions before starting any manipulations.
In this article, we will discuss all the legal ways to enter the test mode, consider the purpose of the main points and answer frequent questions, you will learn how to check the touch screen for dead zones and make sure that the GPS module is healthy before using the navigator.
What is an engineering mode and why you need it on Redmi 8
Engineering Mode is a special diagnostic section in the firmware of the smartphone, created by Xiaomi engineers to check hardware components during the production and repair phase. Unlike the usual settings menu, here the user gets access to low-level tests that run specific components of the device in isolation. For Redmi 8, this is especially true, since hardware tests help distinguish software failure from physical failure.
The main purpose of using CIT is to detect defects, for example, if you have a hard-to-hear audience, the microphone test will show whether the device picks up sound at all. If the screen responds to late-touch touches, the Touchpanel test visualizes the response of the matrix, a powerful tool for initial diagnosis before going to the service center.
⚠️ Warning: Changing the parameters in the sections marked as "Single Item Test" or "Version" may cause the radio module to malfunction or calibrate the sensor.
There is a common misconception that you can unlock a bootloader or get root rights through an engineering menu. It's not. It's designed solely to test and gather information about the state of the iron, and trying to find hidden features here to hack the system is pointless and can confuse the user.
The menu features on Redmi 8 cover almost all nodes, from the vibrator motor and flashlight to the proximity and light sensors. Understanding the working principle of each test will allow you to effectively use your smartphone and monitor its technical condition.
How to enter the engineering menu through codes and applications
The fastest and most proven way to get into the diagnostics section on Xiaomi Redmi 8 is the use of special devices. USSD-These character combinations activate the hidden dialing functions, instantly triggering the desired interface. MIUI Blocks some codes in global firmware, so it’s important to know the current combinations for your version of the software.
To jump to hardware tests, type the following combination in the Phone app: ##6484##. This is the universal code for most Xiaomi devices that opens the CIT menu. If the combination doesn't work, try the alternative ##4636##, which opens the phone information testing menu, even though it contains fewer hardware tests.
- 📱 Enter ##6484## in a standard call – the menu will open automatically without pressing the call button.
- 🔍 If the code doesn’t work, make sure you have it. SIM-map and signal network, as some checks require registration on the network.
- ⚙️ On some versions MIUI Access to the codes may be limited to the operator, then the application will help MIUI Hidden Settings.
Another method of login is through the standard Security app, and some Redmi 8 MIUI builds have a hidden item in the device's check menu, but codes remain the most reliable method, requiring no additional software installation.
If none of the codes activates the menu, your firmware version may have region limitations, and you can use Activity Launcher, which allows you to run hidden system activities, including com.xiaomi.cit.
Step-by-step: login via settings and application
For those who prefer a GUI, there is an alternative way through system settings, a method less well known, but it works consistently on most Xiaomi devices, and it is especially useful if the dial keyboard is not working properly.
First, you need to go to the About Phone section in the basic settings, where you need to find the MIUI version and quickly click on it several times, which usually triggers an update, but when combined with certain conditions, can open access to extended logs.
⚠️ Clicking on the firmware version in normal mode will not open the engineering menu, it will only show the logo. MIUI. For the entrance CIT This method is auxiliary and often requires a special label in the application menu.
A more efficient way to use the settings is to search for a hidden shortcut. In the Security app (green lightning icon), select Memory Clear or Battery. In the upper right corner, a hidden menu sometimes appears, available after a series of taps, but on Redmi 8, the direct path through the settings is often closed.
The most effective software method without code is to use the "Special Features" function. Go to Settings → Advanced Settings → Special. Here you can activate a menu for people with disabilities that overlaps the interface but does not give access to CIT. So for Redmi 8, the code # #6484## remains the only guaranteed way.
Overview of the main tests and functions of CIT Xiaomi
Once you log in, you'll see a list of dozens of items, each of which is responsible for verifying a specific component. The CIT interface on Redmi 8 is minimalist: the name of the test and two buttons, "Pass" and "Fail" (Not Passed), and you need to press the appropriate button to proceed to the next test.
One of the most useful tests is Touchpanel, which turns the screen into a certain color when it starts, and you're asked to swipe your finger over the entire surface, and if the line is interrupted or not drawn in the area, it indicates a defect in the digitizer or protective glass.
The Display test allows you to assess the quality of color reproduction and identify broken pixels. The screen consistently changes colors (red, green, blue, white, black), which helps to notice uneven backlights or color spots that are invisible in normal use.
The Receiver and Speaker section checks the audio modules, in the first case, the sound will go through the top speaker (as in a conversation), in the second - through the bottom multimedia, which allows you to determine exactly which speaker is wheezing or silent.
Hidden tests of the distance sensor
Diagnostics of sensor, display and sound
The detailed touchscreen check on the Redmi 8 is critical, because it's a device that's often used in active environments. On the Touchpanel menu, you can see the location of the tap. Swipe your finger around the perimeter of the screen -- the line should be continuous. Any gaps indicate a problem.
Sound testing involves not only playing the tunes, but also recording. The Microphone test will ask you to say something, and then play the recording, and it's the best way to check if the microphone is dusty and is running at the software level.
For owners using navigation, a GPS test is important, it shows the number of satellites visible and the accuracy of the positioning. If there is no signal in the field, but the test shows the module's operation, the problem may be in the software settings or antenna.
| Name of the test | Function | Normal result |
|---|---|---|
| Touchpanel | Sensor check. | Continuous line across the screen |
| Speaker | Basic dynamics test | Pure sound without wheezing |
| Receiver | Talk dynamics test | A sound is heard in the upper speaker |
| Vibrator | Vibrator check | Sensible vibration of the body |
Don't forget to check the Vibrator. The short vibration confirms that the motor is working, and if the phone is silent in vibration mode, but it works in the test, the problem is the sound profile settings.
Checking communication, Wi-Fi and Bluetooth modules
Wireless modules are complex components of Redmi 8 that require special attention. The engineering menu has tests for Wi-Fi, Bluetooth and cellular communication. The Wi-Fi test will try to scan the available networks; if the list is empty, it is possible that the antenna module is damaged or disabled software.
In the Sim section, the reading is checked SIM-The system will show you the maps. ICCID If you see "No Sim" here when you insert the module, the problem may be the tray contacts or the slot itself.
The Bluetooth test works like Wi-Fi, where you look for neighboring gadgets, and if you find other devices, you can see that the radio is working, and that's especially important if you're using wireless headphones or fitness bracelets.
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If the Wi-Fi test doesn’t find networks, but other tests work, try resetting the network settings in the Android menu before carrying the phone for repair.
To check the signal quality, you use the Phone or RF partition (Radio Frequency) and you can see the signal level in dBm. A value closer to -50 dBm is considered excellent, below -100 dBm is extremely weak.
Sensor calibration and parameter reset
One of the key functions of the engineering menu is sensor calibration. On Xiaomi Redmi 8, the Sensor item is responsible for this, where you can automatically calibrate the accelerometer, gyroscope and magnetometer.
If the screen autorotates incorrectly or the compass shows the wrong direction, recalibration in this menu often solves the problem. Follow the instructions on the screen: usually you need to put the phone on a flat surface or turn it in different directions.
It is important to note that the reset (Clear eMMC or similar items) deletes all data. There are reset items in the CIT menu, but they are dangerous for the average user. Use only calibration functions without affecting the reset sections.
⚠️ Warning: Never press the Clear Flash or Format buttons inside the engineering menu unless you know exactly what you're doing, which can lead to complete data loss and the need to flash through your computer.
After all the tests and calibrations, be sure to restart the device.Some changes only take effect after the full cycle of the Redmi 8.