Service (secret) codes for Android smartphones. Android engineering menu, its capabilities and quick entry Necessary information about the engineering menu in the phone
In order for developers and testers of software and mobile devices to obtain some system information and debug smartphone functions, the Android OS contains some hidden features. Among them are connecting to a PC in developer mode, viewing detailed information about networks and hardware, etc. One of the tools for this is the engineering menu.
The engineering menu is a special settings menu that contains tools for testing and calibrating smartphone hardware. By default, it is hidden, and in order to get into it, you must perform a certain procedure. The appearance of the engineering menu differs on different smartphones, depending on the manufacturer and SoC model. The customization options will also be different.
There are several ways to enter the engineering menu, which differ depending on the smartphone manufacturer and chipset model. You can first try entering one of the codes in the dialer application:
- *#*#3646633#*#* - smartphones with
- *#*#6484#*#* - some smartphones with Qualcomm;
- *#*#54298#*#* - some smartphones with MediaTek;
- *#0*# - some Samsung smartphones;
- *#*#7378423#*#* - some Sony smartphones;
- *#*#4636#*#* - on some devices opens only the network menu;
- *#*#2846579#*#* - some Huawei devices.
If none of the codes help, on your smartphone with MediaTek you should install the program “Launch MTK Engineering Menu” from the market. On Xiaomi devices, you can enter the menu by going to “Settings”, selecting “About phone” and then clicking the “Kernel version” line five times in a row.
What can be configured on a smartphone in the engineering menu
The engineering menu differs on different platforms; in many cases, it only allows you to test some parameters. On Xiaomi Redmi Note 3 Pro and Note 4X, built on Qualcomm chips, the engineering menu allows you to test various functions. These include the screen, sensor, sensors, cameras, sound and microphone, communications, battery, navigation, etc. There is no way to change anything, you can only find out if everything is working correctly.
There are much richer opportunities on the MediaTek platform. In Oukitel U7 Plus (MT6737 chipset), the engineering menu allows you to configure network, sound, communication modules, and other modules. On Redmi Note 2 with MTK Helio X10, the menu was identical, and on other devices with MTK it is not particularly different. We will use his example to describe the possibilities.
Telephony tab
This section is responsible for setting up a cellular modem. Here, interesting possibilities are provided by the BandMode, Network Selecting and GPRS options.
BandMode
In this menu, you can select communication standards that will be active on the phone when connecting to mobile networks. In the menu item, you can select frequency ranges for each SIM card; if there are two SIM cards, the full list is usually available only on the main one (usually the first one). Once you know exactly which frequencies your operator uses in the region, you can uncheck all the others. This will slightly increase battery life due to the fact that the device will not search for operator towers in these ranges, wasting extra energy on scanning the airwaves.
Sometimes some communication standards (especially LTE) are supported at the chipset and core level, but are disabled in the firmware. By checking the box next to them, you can activate support for these networks. It is worth warning that it does not work everywhere: on the same Redmi Note 2 (Chinese version) TDD-LTE was enabled in this way, but on Oukitel U7 Plus these items are not activated.
Network Selecting
The name speaks for itself: this item is also responsible for selecting networks. Only in this case the user can choose which types of networks to use. The goal is the same as in the previous paragraph: to reduce the load on the cellular modem, thereby reducing battery consumption. You can choose to work only in 2G, 3G, 4G, or combine several standards.
If your operator does not have 3G or 4G at all, these items can be disabled so that the smartphone does not constantly try to search for LTE networks, thereby speeding up battery drain. You can also disable 3G and 4G if you need constant communication (for example, for correspondence over the Internet), but traffic is limited and uncontrolled use of WCDMA and LTE by background processes can quickly waste it.
GPRS
Despite the name, this item is not interesting because of the GPRS communication settings, which many people no longer need, and it is not recommended for “mere mortals” to change the settings themselves. The main feature is the ability to record the IMEI of the smartphone. In the appropriate item, you can enter the device identification number and click Write to save it.
The ability to write IMEI is often required after an unsuccessful flashing, when it “flies” and the device cannot register in the operator’s network. By copying this code from the smartphone box, you can restore functionality. Attention! illegally changing the IMEI of a smartphone in many countries (including Russia, Ukraine) is a crime! In addition, by rewriting this code to a random one belonging to another subscriber of your operator, communication problems may occur due to a hardware conflict. Therefore, we recommend that you always keep the box or sticker with IMEI in case of unsuccessful firmware. After all, on devices with a non-removable cover, this identifier is not written under the battery.
Connectivity tab
In this tab, functions for testing and fine-tuning the Bluetooth module, radio receiver and Wi-Fi are available. The vast majority of users have nothing to do here, since there are no settings interesting for a layman, but it’s easy to disrupt the normal operation of Bluetooth by entering something wrong.
Hardware Testing Tab
This settings item in the engineering menu is responsible for the hardware configuration. The Audio and TouchScreen items are of interest to users. The latter contains HandWriting and MultiTouch items. It’s easy to guess what these parameters are responsible for.
Using the first one, you can check the clarity of the touchscreen response and check for the presence of “blind spots”. This menu is especially useful when buying a smartphone, in particular, without a warranty. The second point allows you to do the same, but with the participation of several fingers. With it you can test how well the smartphone processes gestures of several fingers simultaneously.
Audio
It is this treasured item that is needed by those who are looking for how to increase the volume in the engineering menu. The top items allow you to control the volume of the device and are responsible for different modes.
Normal Mode is a mode for normal use, with music or video sounds output to the music speaker. Headset Mode is responsible for controlling the volume in the headphones. LoudSpeaker mode allows you to adjust the conversation volume when using the speakerphone. The last item is a combined one; it is responsible for speakerphone when headphones are connected. In order to change the sound in the engineering menu, you need to select which device you want to configure.
- Sip - settings for Internet telephony;
- Mic - microphone sensitivity
- Sph - conversational speaker;
- Sph2 - second earpiece (a rare beast among smartphones);
- Sid - after changing this parameter, an echo of your voice may appear during a conversation, so you do not need to touch it;
- Media - a multimedia speaker, what most people need.
In order to adjust the volume, you need to go to the required mode (for the volume of a multimedia speaker this is Normal Mode), select the Media item and set the volume value in the specified range.
The Level parameter is responsible for the volume value set by the rocker at each division. Level 0 is the minimum value (one division), the highest Level is all divisions, on Oukitel U7 Plus it is 14, on other smartphones it may differ. The value can range from 0 (speaker silent) to 255 (full volume). There is no particular point in changing the value, but if after a certain division it seems to you that the sound suddenly becomes much quieter, you can increase the values for this division (and lower levels) by a couple of units. The main thing is that the conditional Level 6 does not turn out to be louder than Level 7 due to the value being too high.
But to increase the maximum volume in general, you need to change the value in the Max Vol item. The maximum level corresponds to 160, but manufacturers often set it lower (on the tested device it was 128). By setting the number higher, the volume will increase, but there may also be side effects such as gurgling, noises and wheezing. The optimal value should be selected using the scientific method: increase the value by several units, save, check the sound on video or music, and if everything is fine, increase it further.
Conclusion
It’s worth repeating once again that the engineering menu is different on different smartphones. What is available on the MediaTek platform cannot be done on Qualcomm. Codes for entering hidden settings may also not be suitable in some cases; we cannot guarantee their 100% functionality. In addition, everything you do with your smartphone is done at your own peril and risk, since incorrect settings can affect its performance. In such cases, only a general reset or flashing will help. So if you really want to experiment with settings whose meaning you don’t fully understand, it’s advisable to take screenshots before doing so, so that if something happens, you can enter the factory values.
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The engineering menu on Android devices is a special “built-in” application into the operating system that allows you to fine-tune the device. This is necessary to debug the operation of the hardware and, of course, the software. But often users want to change some settings at their own discretion. In this case, the question arises of how to enter the Android engineering menu. This can be done with special service codes or third-party software.
What options does the engineering menu have?
Settings and menu design on Android devices may vary depending on the phone manufacturer. In general, users resort to using the engineering menu for the following reasons:
- Setting up audio on the phone (ringer volume, interlocutor’s voice during a conversation);
- Changing camera settings;
- Using recovery mode;
- Setting microphone sensitivity;
- Disabling unused frequencies to save phone battery;
- Obtaining information about the device's MAC address;
- Setting up Bluetooth and Wi-Fi.
The Android engineering menu provides the user with almost limitless possibilities. But you should always remember that only advanced users can use it. Changing some settings may cause your smartphone or tablet to not work correctly. If you don't know what each menu item directly does, simply leave it alone.
The developer mode includes setting up Hardware Testing equipment and also contains the following items:
- Audio – volume control in the phone speakers.
- Camera – allows you to configure various camera parameters (image size, type, etc.).
- Diving current camera shows the current of the camera.
- CPU Stress Test performs a test load on the central processor.
- De-sense is a device manager that manages configuration parameters.
- Display – setting the frequency of the outgoing signal.
- IO – setting up input/output operations.
- Memory – key information about memory.
- Power – information about the battery.
- SD Card Test - testing a memory card.
- TouchScreen – setting up the touch screen, checking sensitivity.
- USB - Tests the operation of the USB port on your phone.
In the Connectivity tab you can get information about devices that work with the outside world. These include Bluetooth, Wi-Fi and FM module. The Log and Debugging tab allows you to view the battery log, set the debugger level and run a special MTK log. In the Others tab, you can change fonts, as well as view the temperature of the processor and battery.
How to enter the engineering menu: using code combinations
To enter the engineering menu as quickly and easily as possible, you will need special engineering codes. Each manufacturer has its own combination, which opens access to the engineering menu in Android.
To enter the menu you need to:
In most cases, this technique allows you to open the service menu. Below are some combinations for the most popular phones:
- Models from HTC - *#*#3424#*#*, *#*#4636#*#* or *#*#8255#*#*;
- Samsung devices - *#*#197328640#*#* or *#*#8255#*#*;
- Sony smartphones - *#*#3646633#*#*, *#*#7378423#*#* or *#*#3649547#*#*;
- Huawei phones - *#*#2846579#*#* or *#*#14789632#*#*;
- Mobile from ZTE - *#*#4636#*#*.
There is also a universal code that is suitable for most smartphones and tablets running on an MTK processor. You can look in the specifications of your device to see what processor you have installed. If this is a MediaTek (MTK) product, then try using the combination *#*#54298#*#* or *#*#3646633#*#*.
If it works, you will see the developer menu in front of you. Some engineering codes for Android do not work in operating versions 4.2.1 and 4.2.2.
What third-party applications can be used to enter the engineering menu
How to enter the engineering menu on Android if the Android codes do not work? There is a way. To enter the engineering menu, you will need one of the applications that will allow you to enter developer mode without entering a combination. There are several similar programs in the official Google Play store. One of them is “Launch the MTK engineering menu”.
To use it, you need:
- Go to the Play Market and enter the name of the program in the search bar.
- Download and install it.
- Launch on your phone.
After that, you will see a couple of tabs with different settings.
The application allows you to perform various tests (for example, a processor stress test), obtain information about the modem or memory, and much more. You can also make changes to the hardware. To do this, you just need to open the appropriate sections and configure the settings. In this case, the phone will be on all the time.
An alternative option is the Mobileuncle tools program. You can download it on the Internet. Install the application, and then go to the “Engineer Mode” submenu. Almost all developer menu items will be available in it.
Surely not many users of Android OS devices know that there are so-called engineering (service) codes, which, by the way, appeared much earlier than the release of the first version of the Android OS. This set of special characters was called by the developers the “Engineering Menu”, which is recommended to be manipulated only by specialists, but, nevertheless, for ordinary users this kind of information will clearly be of interest and probably useful.
The main purpose of this system is for service center specialists to work with it to repair and fine-tune mobile devices. Therefore, after reading this material, and having learned the combination of symbols for entering this or that block of the engineering menu, you decide to experiment with your own device, without sufficient knowledge and training, you must be aware that all responsibility for the consequences will lie only with you.
What can be changed in the engineering menu
Now we will tell you what can be done using this or that engineering code:
Engineering menu codes and their functions:
- Find out the IMEI identifier - *#06#
- Settings and details - *#*#4636#*#*
- Android firmware, version - *#2222#
- Delete all SMS - #*5376#
- Getting information about the phone (usage statistics) and battery - *#*#4636#*#*
- Resetting the phone owner's Google account settings and other system utilities without removing pre-installed software while preserving programs located on the memory card (SD) - *#*#7780#*#* (before resetting the settings, you will be asked to confirm the action being performed, so there is still a chance to change your mind).
- Performing a factory format - deleting absolutely all settings and files, including those stored in the internal memory, and reinstalling the smartphone firmware - *2767*3855# (Entering the code does not give you a chance to think twice; only quick removal of the battery and data recovery via PC is possible)
- Camera Information - *#*#34971539#*#* Here you can work on the following parameters:
— updating the phone camera firmware into an image,
— Obtaining the firmware version,
— information about the number of firmware updates,
— updating the camera firmware on the SD card.
Important! You should NEVER use the first option yourself to avoid complete failure of the camera.
- Changing the End End button modes (On/Off) — *#*#7594#*#* By default, a long press of the button shows on the screen options for switching to silent mode, flight mode, or turning off the smartphone. Here you can turn off your phone automatically without selecting any options.
- Opening the file copy screen - *#*#273283*255*663 282*#*#* Here it is possible to obtain backup copies of your own data (photos, audio, etc.).
- Entering service mode (running various tests (by pressing the “menu” button), changing settings in service mode) - *#*#197328640#*#*
Factory test codes:
- Wi-Fi MAC address - *#*#232338#*#*
- WLAN - *#*#232339#*#*
- GPS test - *#*#1472365#*#* or *#*#1575#*#*
- Bluetooth *#*#232331#*#*
- Bluetooth address - *#*#232337#*#
- Loopback Batch Tests - *#*#0283#*#*
- Touch Screen Version - *#*#2663#*#* (test *#*#2664#*#* )
- Motion sensor test - *#*#0588#*#*
- LCD test - *#*#0*#*#*
- Vibration and backlight - *#*#0842#*#*
- Melody test - *#*#0673#*#*
- RAM version - *#*#3264#*#*
We have provided information only about basic codes for Android that solve some problems in the operation of the device and therefore may be of interest to advanced users. But, nevertheless, let us remind you once again: DO NOT enter any codes if you do not know what they are for!
To enter the Engineering Menu, instead of a phone number, you need to enter a certain combination of characters into the dialer, different for different manufacturers:
- For Samsung - *#*#8255#*#* or *#*#4636#*#*
- Smartphones based on MTK processors - *#*#3646633#*#* (Maybe *#*#54298#*#* )
- "HTC" - *#*#8255#*#* or *#*#3424#*#*
- "Sony" - *#*#7378423#*#*
- Huawei - *#*#2846579159#*#* or *#*#2846579#*#*
- Fly, Philips, Alcatel - *#*#3646633#*#*
Immediately after entering, the engineering menu should open. If it doesn't work, you can try pressing the button that makes the call.
To launch the engineering menu on smartphones with an MTK processor, there is a special application that can be used if the service does not open through the dialer.
In fact, as can be seen from the material, the service menu opens up enormous opportunities for setting up or troubleshooting problems in the device, but amateurs should still not use it in order to avoid “bricking” their “Andryukha”. Take this note into account if your little hands are itching to urgently enter the treasured code.
Modern smartphones are not only an opportunity to make calls, surf the Internet and try out various games. Devices running the Android OS have a fairly large number of different secrets and extensions. Some of them are available in the engineering menu. But what is it? How to enter the engineering menu? Are there any risks in working with this part of the gadget’s firmware? Let's start with the question of why this menu is not publicly available.
Safety
The fact is that everything that the user has access to, even if mishandled and deleted, will not cause irreparable harm to the smartphone. This same menu, if used incorrectly, can lead to the fact that the gadget is not much different from a simple tin can, which belongs in the trash can.
In addition, everything that the user really needs is always available to the public. Hidden functions are more intended for those who are professionally involved in software repair of smartphones. By the way, many experts recommend taking a piece of paper and a pen before entering the Android engineering menu. For what? Just in case, record all the stock data. This comes in handy when something goes wrong.
What is this menu?
The engineering menu refers to a special program used by developers at the end of the formation of the gadget’s software platform. At the final stage, it helps to change the performance of the device and adjust its various functions at the software level. The same menu is used for testing.
Before using this menu, you should make sure that your smartphone runs on a MediaTek processor. Why is this so important? On other chipsets, for example, Qualcomm, the engineering menu is noticeably truncated and may be completely absent. How to enter the Samsung engineering menu is not a question at all, since all devices of this brand run on other types of processors.
Android version
Is there a difference between how to enter the engineering menu of Android 5.1 and a younger or older version of the platform? Note that there is a difference even in brands and models of gadgets. As mentioned above, for Samsung there is no entry to the engineering menu, although some claim that in this case the following commands work: *#*#8255#*#*, *#0011# or *#*#4636#*#.
How to open the menu
And now we come to the main question: how to enter the engineering menu? This is possible if you enter a special code. This can be done through the dialer. What should I enter?
- *#*#3646633#*#*
- *#*#4636#*#*
- *#15963#*
After entering the command, most smartphones are automatically redirected to the engineering menu. In rare cases, you need to press the call button. If nothing happens after this, check that your input is correct. If there is no error, but no result, then the entered code does not suit you.
If you have a tablet that does not have a dialer, or none of the codes worked, you can download a special application from the Market. For example, MTK Engineering or MobileUncle Tools. The apps are free.
Functional
After you have succeeded in entering the engineering menu, you need to find the department for which all the procedures described above were performed. There are three options to test and determine any indicators. Let's figure out what's what.
Camera
Let's start, perhaps, with this part of the gadget. Through the engineering menu you can configure almost all camera parameters. In another mode, you can turn it on to determine operating current indicators. Few people are interested in this, but in some cases it helps solve certain problems associated with auto-correction or focusing.
Audio
Often, the question of how to enter the phone’s engineering menu interests the user precisely because he wants to make his gadget louder. If the manufacturer has not set the maximum settings, you can independently adjust the sound in both the speakers and microphone.
These operations can be carried out in several separate modes:
- Sip. This item is designed to set up calls via the Internet according to parameters convenient for you.
- Mic. In this section, you can change the sensitivity of the microphone in any direction, for example, make it so that the microphone does not pick up breathing, and so on.
- Sph. This section is responsible for the auditory speaker. It is recommended to use it if you have difficulty hearing interlocutors calling from different devices, and adjusting the volume rocker does not help.
- Sph2. This function cannot be used in every smartphone, since it is intended for the second hearing speaker.
- Sid. It is better not to change this parameter, since it is almost impossible to configure it correctly again. It is responsible for the echo effect.
- Media. Use this section if you are not satisfied with the multimedia volume level. Here we are talking about music, video and so on.
- Ring. The name of this parameter speaks for itself - ringtone or volume of an incoming call.
- FMR - radio sound settings.
When working in each section, you should understand that you should not play with each of the parameters.
Connections
In the connections section, you can test and adjust all possible types of connections that the gadget has. These include Bluetooth and Wi-Fi. In addition to these obvious types of wireless connection, you can check how well and stable the WLAN CTIA and even the FM receiver are.
Interestingly, in a separate section “Disable detection” you can adjust the signal frequency.
Display and touch screen
These sections will help you test and configure your smartphone screen and backlight. The first is responsible for correcting the backlight, controlling the display lines and adjusting the backlight. When setting up the sensor, you can test it for broken segments, response to touch, and so on. You can also calibrate the sensor through the engineering menu.
Memory and USB
The question of how to enter the engineering menu is also asked by those who are faced with the disappearance of memory on the device. By the way, in a separate section you can test the SD card. As for the gadget’s memory, the menu contains all the information about the module. In the engineering menu you can test the functionality of the USB port.
Battery
Quite a lot of people search for this section and get upset when they don’t find it. Maybe it's not in the engineering menu? In fact, you can see the condition of the battery, the percentage of its wear and the rating of the processes that most affect the device in the “In Degree” section and in the “Battery Log”. The reason for such a strange name is an incorrect translation from English. By the way, there is simply no transition from Russian to any other language in the engineering menu.
Qualcomm
As mentioned above, in most devices with such a processor, the engineering menu does not work or is significantly reduced. You can get into it through the regular menu. In it you need to click on the item called “Kernel Version” several times in a row. A new function will open to you, which contains five separate items. Which ones?
- Automatic Test. Fully consistent with its name, it carries out automatic testing of all necessary systems.
- Single Item Test. This section allows you to choose one of 25 tests.
- Test Report. Clicking on this option will allow you to view test reports.
- SW add HW version consists of various numbers that display the smartphone data.
- Device View. Here you can find information about the equipment.
Not all Qualcomm smartphones will display exactly this menu, but it’s worth a try.
conclusions
Knowing how to enter the engineering menu of “Android 4.4” and other versions of this operating system, you should understand that if one of the settings causes the gadget to malfunction, the ability to restore it becomes very small. Therefore, as soon as you decide to change anything in the settings through the engineering menu, be aware that this could end the life of the device. If you are not satisfied with something in the operation of the gadget, it is better to contact an experienced technician and describe your wishes in detail. He will be able to soberly assess the possibilities and make a verdict.
We are all familiar with the rich settings of Android devices - each smartphone or tablet can be customized by activating or disabling certain functions, adjusting certain parameters. But few people suspect the existence of such a thing as the Android engineering menu. It is hidden from view, since there is nothing special for the average user to do here. But if you are an experienced user or want to gain experience in fine-tuning the device and operating system, then this menu will be useful to you.
Let's figure out why we need an engineering menu in a smartphone? The answer is simple - for very fine tuning of the device. For example, increasing the volume on Android is only possible through the engineering menu. Here you need to visit the audio settings item and play with the presented parameters. Here it is possible to manually adjust the sound volume in various modes and at various volume levels.
Let's look at an example:
- You find that your smartphone's speaker starts to wheeze at maximum volume;
- We go to the engineering menu using one or another command;
- Go to the audio settings and change the volume in the specified mode and in the specified gradation;
- We exit the engineering menu and check the results - the volume should decrease.
Is it possible to make such fine adjustments only through the standard setup menu? Naturally, there is nothing of the kind here.
Here you can adjust the sound in the headphones, adjust the sensitivity of the microphone, and perform other actions with the sound. Before getting into the settings, you need to find detailed instructions that will help you make the adjustments as correctly as possible, without the risk of damaging the speakers with a microphone or completely depriving your smartphone/tablet of your voice.
What other functions are there in the engineering menu? Checking network modules, adjusting the reception range, setting up auto-answer, testing the modem, setting up connections with other devices, setting up the receiver, testing the camera, sensor, screen, battery and other modules.
Geolocation settings are placed in a separate hidden menu– here you can check the functionality of the GPS chip, enable/disable A-GPS, and check other settings. It is also possible to adjust fonts, play with USB settings and perform other actions.
Please note that the service menu on Android is intended for professionals who are aware of their actions. If you came here out of idle curiosity, try not to touch parameters you don’t understand and don’t rearrange the settings sliders.
How to enter the engineering menu on Android
Entering the engineering menu on Android is most often done using special commands, similar to the most common USSD commands. The difference is that you don’t need to press the call button at the end - after typing the command, it will automatically transfer to the specified menu. The universal code for the engineering menu on Android is *#*#3646633#*#*. It works on many phones and allows you to instantly enter service settings.
Some smartphones and tablets do not respond to the above command. So you can try the following options:
- *#*#4636#*#*;
- *#15963#*;
- *#8255#*;
- *#*#7378423#*#* (for Sony smartphones);
- *#*#3424#*#* (code for HTC smartphones);
- *#*#2846579#*#* (code for Huawei smartphones).
You can enter the engineering menu on Android immediately after entering the command. There is no dependence on the operating system version - the codes are valid for Android 2.2, Android 4.4 and other versions of Android OS. If the code does not fit, you should look for other combinations.
Some commands lead not to the service menu, but to the testing menu - it allows you to check the screen, sound, wireless modules, microphone and much more. Menus for testing can be English or Russified.
Some manufacturers deprive smartphones and tablets of access to the engineering menu, replacing it with numerous commands for testing modules or configuring certain parameters. For example, this is what Samsung does - many new models do not have a single service menu. Information about available service teams can be found on specialized resources and on the websites of service centers.
To access the engineering menu, you can use special applications. A typical example is the Mobileuncle MTK Tools application. It will allow you to gain separate access to device settings and operating system settings. The application is really convenient, but it has a drawback - it only works on devices with MTK processors.
If your smartphone/tablet runs on a different platform, you can try looking for alternative applications to access the engineering menu on Android.
Setting up Android through the engineering menu is associated with certain risks. For example, beginners always have the opportunity to accidentally disable this or that functionality. When understanding the purpose of certain items, you need to familiarize yourself with the appropriate instructions. Otherwise, equipment failure may occur. If you are afraid of damaging or breaking something, make a complete backup of your device - in case of a fatal error, you can perform a Hard Reset and restore your smartphone or tablet.
Never enter commands whose purpose you do not know. The thing is that some of them are designed to quickly change critical system parameters or perform a general reset. Moreover, some commands perform a general reset without confirmation, instantly erasing all contents.
