Many owners of smartphones Xiaomi, Redmi and POCO Sooner or later, they notice that the device begins to discharge faster than usual or behaves unpredictably. Often users are looking for a magic combination of numbers that will instantly show the real state of the battery, but there is no universal “secret code” for deep diagnostics in the form in which it is presented on the Internet. Instead of a single magic number, the company’s engineers have implemented a whole range of diagnostic tools available through special special devices. USSD-requests and hidden menus.
The most common myth is that code ##64663##, or its variation ##6484###, can work wonders. In fact, this sequence opens up the CIT (Customer Information Test) engineering menu, which was originally designed to test devices before sale, and is where the tools for detailed battery capacity, voltage and charge cycles, which is much more informative than the standard status bar percentage display, hide.
It is important to understand that access to these features may vary depending on the shell version. MIUI or a new HyperOS. Some carriers block execution USSD-In these cases, you will have to look for alternative ways to enter the diagnostics, and below we will discuss in detail how to use these tools correctly to get honest information about the health of your Li-Po or Li-Ion battery.
To run a full diagnostic, you don't need superuser rights or a computer connection. All the tools are already built into the firmware, but hidden from the eyes of the average user. The fastest way to activate this mode is to use the standard Phone or Caller app.
Type one of the following combinations on the keyboard. Usually the system responds instantly and the menu opens automatically, without having to press the call button. If one combination fails, try the alternative one, as they can vary depending on the regional version of the software.
- 📞 ##64663## - the main code for entering the CIT
- 📞 ##6484## - an alternative for some models
- 📞 ##4636## - Menu of phone information (less detailed)
- 📞 ##225## - Calendar information (sometimes containing data on food events)
⚠️ Warning: Do not change settings in menu items whose value you do not know. Accidental activation of test modes of the radio module or calibration of the sensor without need can lead to improper communication or touch screen.
Once you code in, the screen changes, and you see a list of tests with the names of the components: Display, Touchpanel, Receiver, Battery. We're interested in the item that's connected to the grid. It can be called differently in different versions of MIUI, but most often it's just Battery.
📊 How often do you check the battery status?
Every day.
Once a week.
Only when the phone goes down quickly.
Never checked.
Detailed check of battery status
Once inside the Battery, the user can access raw data that is read directly from the power controller, and there are no beautiful graphs, only technical parameters that allow you to assess the physical wear of the battery. The key indicators are the current voltage, temperature and, most importantly, status.
Note the Battery Status line. It should say, "Good" or "Charge" in perfect condition. If you see messages like "Over Voltage," "Over Temperature" or "Dead," it's a critical malfunction that requires immediate intervention. And the Technology parameter that confirms the type of battery chemistry.
Temperature is a critical parameter for lithium batteries, and when it's down, it should not exceed that. 35-40 If the sensors are at rest, they may have an internal defect or a background process that causes the mothers to overheat.--
Oh, pay.
What to do if the battery status is "Over Voltage"?
This means that the battery voltage has exceeded the permissible limit (usually higher). 4.35-4.4C. You must immediately stop charging, turn off the device and let it cool. Continuing to operate is dangerous to the risk of bloating or fire. Decoding the codes and diagnostic parameters of the Engineering Menu interface can seem intimidating due to the abundance of technical terms in English. To keep you from guessing what each row means, we have prepared a table decoding the main parameters that occur in the section of the power diagnostics. Parameter Description Normal value of Battery Status General battery status Good / Charge Level Current charge in percentage 0-100% Scale Maximum Charge Scale 100 Voltage Current voltage (mV) 3700-4200 MV Temperature Battery Temperature (0.1°C) 250-400 (25-40°C) Special attention should be paid to the Voltage parameter. The voltage of a fully charged lithium polymer battery is about 4200-4350 m (4.2-4.35 B. If the phone is showing 100% charge, but voltage is lower 4000 mV is a sure sign that the battery has lost its capacity and needs to be replaced, and some firmware versions also feature the Design Capacity and Current Capacity option. Comparing these two numbers gives the most accurate idea of the degree of degradation, if the current capacity is less than 80% The battery is considered to have exhausted its life and must be replaced for comfortable use. CIT The engineering menu is not just designed to test the battery, it allows you to diagnose almost all components of the smartphone, which is especially useful when buying a used device or after a fall. By going through the test list, you can detect hidden defects that are not visible in normal use, such as the Touchpanel test, which allows you to check the touch screen for dead zones or false positives. You're going to be asked to swipe through the circuits of the screen, and the system will illuminate all the areas you've walked, and this is an indispensable tool for checking the quality of the display after you've changed the glass. 📷 Camera – check the focus and operation of all camera modules 🔊 Receiver / Speaker – test of the sound speaker and the conversational speaker 📶 Wi-Fi / Bluetooth / GPS — check of antennas and communication modules 💡 LED / Flash - flash test and notification indicator Don't ignore the vibration test (Vibrator). Often it is the vibrator that fails first after moisture hits, and its verification takes only a couple of seconds. If the phone vibrates when the call is incoming, but the test is silent, this is an excuse to check the appropriate settings or contact the service. Alternative ways to check the battery health If the input through secret codes is blocked or not working for some reason, there are other methods to obtain information about the battery status. These can be less detailed, but often more convenient for the average user. The easiest way is to use the Security app, which is preinstalled on all Xiaomi smartphones. The Battery section often displays temperature and approximate operating time. However, to get accurate data on charge cycles and real wear, it is better to use the software from the rootBat application, it requires the application to install the root mode. After a few days of use, it will be able to show the real residual capacity of the battery in mAh and compare it with the manufacturer's stated capacity. ⚠️ Note: Battery calibration applications that promise to “restore” the battery software are a myth. Chemical wear cannot be corrected by code, such applications only reset the statistical file of the system, which may temporarily improve the display of interest, but will not prolong the life of the battery. Even when people know the secret codes, they may encounter situations where the diagnosis does not give the expected result or shows errors, most often problems are associated with software failures of the power controller or unoriginal components. If after replacing the battery, the phone continues to discharge rapidly or shows an incorrect percentage of charge, a reset of battery statistics may be required. This can sometimes be done by completely discharging the device before turning off and then charging the phone to 100% off. In cases where the engineering menu shows the status of "Unknown" or "Not Present", check the battery connection plume. Oxidation of contacts or poor fit of the connector often leads to the fact that the system does not see the battery correctly, although it is physically healthy. 💡Software resetting battery statistics only helps if the controller has forgotten the calibration points, but does not restore the chemically aged battery. Is it safe to enter secret Xiaomi codes? Yes, enter codes in the menu CIT (##64663##) is completely safe, as it is a regular diagnostic feature. However, running tests inside the menu (for example, a recording device test or resetting settings) can change the state of the phone. Why the code ##4636## Does it open the menu? On modern versions of Android and the shell MIUI/HyperOS Access to this code is often restricted to the manufacturer or carrier for security reasons. CIT ##64663## or third-party apps like Phone Info SAM. How do you know how many charge cycles Xiaomi has? Xiaomi's standard engineering menu rarely displays the exact number of cycles. ADB-commands via computer (adb shell dumpsys batterystats) or specialized applications requiring root rights, such as Battery Charge Limit. 1% It turns off, even though the battery is full. What do you do? It's a sign of the controller's desynchronization and the actual capacity. 0% (until it is turned off, then charge to 100% off-set. If the problem persists, the battery is physically worn out. Can a secret code increase the battery capacity? No, it's physically impossible. The software code can't change the chemical composition of the battery or increase its physical volume. All claims of "unlocking the hidden capacity" are marketing hoaxes.