How to view the engineering menu on Android: a complete guide

If nothing happens after entering the code, it means that the manufacturer of your smartphone has blocked this access method through a standard dialer. V takom sluchae sistema prosto ignoriruet vvod, ne vydavaya oshibok. Don't panic, there are alternative software methods, which we will talk about below.

Specific codes for popular brands

Large smartphone manufacturers often implement their own unique access codes that work only on their devices. This is due to the features of branded shells, such as OneUI, MIUI or ColorOS. Knowledge of these specific combinations greatly simplifies the diagnostic task.

For device owners Samsung there is a powerful hardware testing tool. Entering the code #0# immediately opens a grid with screen tests (Red, Green, Blue), sensor check (Touch), vibration and sensors. Eto menyu ne trebuet podtverzhdeniya i rabotaet dazhe bez SIM-karty. For deeper network settings on Samsung, a code *#2263#is sometimes used that allows you to select the preferred frequency range (Band Selection).

Users Xiaomi, Redmi and Poco may encounter limitations in global firmware. Ctandartnyy kod ##6484## ili ##4636## mozhet ne srabotat. In such cases, entering a code ##3646633## (for MTK processors) or using a special CIT (Calibration & Test) application, which is preinstalled in the system but hidden from the launcher, often helps.

Processor-based devices MediaTek have the most open engineering menu architecture. The code ##3646633## gives full access to the radio module settings, audio and hardware tests. Phone owners Meizu, Oppo and Vivo can also often use this code if their device has an MTK chipset.

⚠️ Attention: On some new Huawei and Honor models, access to the engineering menu through codes is completely blocked by the manufacturer for security reasons. To access, you may need a special code calculator, which changes with each firmware version.

Using third-party applications for access

When standard USSD codes are blocked by the manufacturer, specialized applications from the Google Play Market come to the rescue. These apps act as an intermediary, causing hidden system activities through standard Android intents. This is a legal and safe way to access the functions you need.

One ​​of the most popular tools is the application MTK Engineering Mode. It automatically detects the processor type and opens the appropriate menu. For devices on processors Qualcomm there are analogs, for example, QuickShortcutMaker. This application allows you to find the hidden “Engineering Mode” shortcut in the list of all installed apps and create a link to it on your desktop.

The process of using such utilities is extremely simple. Posle ustanovki vam ne nuzhno vvodit dlinnye kombinatsii tsifr. Just launch the application and it will redirect you to the desired section of the system settings. Some apps also provide convenient navigation through complex engineering menu items, translating technical terms into understandable language.

• 📱 MTK Engineering Mode is the best solution for phones on MediaTek chips. Opens the Hardware Testing, Settings and Telephony tabs.
• 📱 QuickShortcutMaker is a universal tool. Allows you to find any hidden menu item by name and create an icon for it.
• 📱 Phone Info SAM —a specialized application for Samsung that shows detailed information about the network and allows you to change some settings via the API.
• 📱 TestM —an application for comprehensive testing of hardware (screen, sound, sensors) in a convenient gaming format.

Important download such utilities only from official sources to avoid malware. Although the applications themselves do not require superuser rights, they do require permission to make calls and access the phone's status, which is necessary for correct operation of the radio module.

Main sections and secure settings

After successfully entering the engineering menu, you will see many tabs and items, the names of which may frighten an inexperienced user. Let's look at the main sections that you may encounter and determine which of these can be touched and which are better left untouched.

Section Telephony or Communication is responsible for the operation of the radio module. Here you can select your preferred network type (for example, only LTE or 3G), view the signal level in dBm and select a specific operator. The Set Preferred Network Type tab allows you to switch the modem operating mode, which is useful if the phone is constantly “jumping” between communication standards.

In the section Hardware Testing tools for checking components are available. You can run the speaker (Receiver), microphone (Mic), vibration (Vibrator) and screen backlight (LCD) test. These tests are indispensable when buying a used phone or after the device has been dropped, when you need to quickly identify a fault.

Particular attention should be paid to the section Bluetooth i Wi-Fi. Here you can test the signal strength and start the pairing procedure in a special mode. However, changing the transmit power parameters (TX Power) without good reason is not recommended, as this may lead to overheating of the module or violation of legal regulations.

Path to network setup (example for MTK):
Engineer Mode → Telephony → Network Selecting → Set Preferred Network Type
Select: LTE Only (for forced 4G)

⚠️ Attention: Never change the values in the "IMEI" or "NVRAM" section. Writing incorrect data to these sections can lead to the loss of a unique device identifier, after which the phone will no longer see the network at all, and restoration will require the intervention of a service center with a programmer.

Battery and screen diagnostics

One of the most common reasons for accessing the engineering menu is to check the battery condition. The stock Android interface often only shows the charge percentage, hiding the actual battery health (SoH). In the service mode, you can see the voltage, temperature and charge status in real time.

To check the screen, use the section LCD or Display. Tests for dead pixels (alternately coloring the screen red, green, blue and white) and checking the backlight uniformity are available here. You can also test multi-touch by drawing lines on the screen - this will help identify the “dead zones” of the sensor that are not visible during normal use.

If you notice that the phone is quickly discharging or heating up, go to the section Battery Log (if available). There you can see the history of charge cycles and current capacity. Comparing the rated capacity and the current calculated capacity will give you an idea of ​​how worn your battery is. If there is a significant loss of capacity (more than 20%), you should think about replacement.

Testing of proximity and light sensors is also carried out here. Incorrect operation of the proximity sensor results in the screen not turning off during a call, which can cause accidental ear taps. Calibration of these sensors is often available directly from the engineering menu through the button Calibration.

Frequent problems and ways to solve them

Users often encounter a situation where, after unsuccessful experiments in the engineering menu, the phone stops receiving the network or not all functions work. Most of these problems can be solved programmatically without the need to go to the service.

If the Internet or the 4G icon has disappeared, check the settings of your preferred network. You may have accidentally set the mode 2G Only or 3G Only. Return the value in LTE/WCDMA/GSM Auto. If this does not help, try resetting the network settings through the standard Android menu: Settings → System → Reset settings → Reset Wi-Fi, mobile data and Bluetooth settings.

In cases where the phone does not see the SIM card at all after changes in the engineering menu, a complete data reset may be required. Before doing this, be sure to save important contacts and files. Sometimes re-registering on the network helps: turn on and off “Airplane Mode” several times in a row with an interval of 10 seconds.

If you have changed the sound and dynamics settings, and the sound has become quiet or hoarse, find the section Audio -> Debug Info or Speechin the engineering menu. There is often a button Set Default or Restorethat returns the factory gain levels for the microphone and speaker.

Remember that the engineering menu interfaces may differ even within the same model if different firmware versions are installed. What was available in the January build may be hidden in the March security update. Always check the current documentation for your specific software version.