How to safely go to the service menu Xiaomi: instructions for smartphones and TVs

Why You Need to Access Xiaomi’s Engineering Menu and When to Use It

Xiaomi’s service (engineering) menu is a hidden settings section that the manufacturer leaves for testing equipment, diagnosing faults and fine-tuning hardware. Unlike the standard MIUI or PatchWall interface (for TV), you can check the display, battery, communication modules and even change parameters that are not available in normal mode.

But it's important to understand that it's a tool for power users and service centers, and that doing something wrong can lead to a loss of warranty, a failure of your device, or even a complete failure, for example, changing the settings of your radio module on your smartphone without knowing the operator's network settings can leave you without mobile connectivity.

When should I go to the service menu?

• 🔧 Diagnostics of hardware problems (for example, checking the operation of the sensor, speakers, microphone).
• 📡 Network signal quality testing (useful in areas with poor coverage).
• 🔋 Checking the real state of the battery (voltage, temperature, wear and tear).
• 🖥️ Customization of screen settings (color temperature, refresh rate) on Mi TVs TV.

If your goal is to just speed up your smartphone or change the theme, the service menu won't help. There's a standard MIUI setting or the Theme app for that, but for deep diagnostics or crash recovery, it's an indispensable tool.

How to go to the service menu on Xiaomi smartphones (all models)

The way you log in depends on the MIUI version and the device model. Most Xiaomi, Redmi and POCO smartphones use a universal code, but there are exceptions. For example, on older devices (before MIUI 10) another method could work.

The main way:

1. Open the Phone app.
2. Enter the combination: ##4636###.
3. On the screen will appear the Testing menu with tabs Phone information, Battery use, etc.

Alternative codes for different models:

If the code doesn’t work, try the following:

• 📱 Make sure that SIM-Card inserted (some codes require an active network).
• 🔄 Reboot the phone and re-enter.
• 🛠️ Update. MIUI Up to the latest version (old firmware codes may not work).

⚠️ Note: Some models (e.g. Xiaomi) 12T or Redmi K50) The engineering menu is blocked by the manufacturer. ADB or root may result in loss of warranty.

Make a backup copy of the data|Charge the battery at least 50 times%|Record the current network settings (APN, point)|Do not change the parameters unless you are sure of their value.-->

Service menu on Xiaomi Mi TV: step-by-step access

On Xiaomi TVs (Mi TV 4/5, Mi TV Q1/Q2, Redmi Smart TV), the service menu gives access to panel settings, sound, HDMI ports and even allows you to reset the time meter.

Instructions for most models:

1. Turn on the TV and go to the main screen of PatchWall.
2. On the remote, press sequentially: Menu → Settings (⚙️) → All settings → The device → About this device.
3. Find the Android TV version and quickly click on it 5-7 times in a row (as when you activate the developer mode).
4. You are a developer!... Go back to the main settings menu.
5. Now in the Settings → Device will appear a new item Service menu.

On some models (e.g., Mi). TV Stick or Mi Box service menu available via ADB-For this, for this:

1. Connect the device to the PC via USB (enable debugging over USB in the developer settings).
2. Enter at the terminal: adb shell am start -n com.android.tv.settings/.device.devicesettings.DeviceSettingsActivity

What can be done in the TV service menu:

• 📺 Check the actual screen resolution and refresh rate.
• 🔊 Calibrate the sound (volume levels, channel balance).
• 🔌 Testing ports HDMI/USB workable.
• ⚡ Reset the counter of the development of lighting lamps (useful when selling TV).

⚠️ Warning: Changing the White Balance or Backlight settings without special equipment (colorimeter) can lead to color distortion, which will be difficult to correct.

What settings can be changed (and what can not be touched)

The service menu provides access to dozens of options, but most of them are for Xiaomi engineers. Below is a list of safe sections that can be used without risk:

It is absolutely forbidden to change the following parameters (this can lead to irreversible consequences):

• 🚫 NV Items (modem settings) – the risk of losing the network forever.
• 🚫 RF Calibration – Calibration of radio frequencies (requires special equipment).
• 🚫 Factory Reset Protection – Can block the device.
• 🚫 Secure Boot – Changes will lead to bricks).

If you accidentally change the critical parameter, immediately:

1. Reset the device.
2. If the problem persists, reset via Recovery Mode (press Power + Volume Up when turned on).
3. In the extreme case, reflash the device through the Mi Flash Tool.

💡

Before any changes, take a picture of the original settings of the screen with the parameters, which will help to bring everything back if the colors or brightness become incorrect.

Diagnostics of the battery through the service menu: what do the numbers mean

One of the most useful sections is Battery Information, where you can see the actual battery status that doesn't show the standard MIUI interface, for example, if the phone is running out quickly, you can see if the battery is to blame or if there's a software problem.

The main parameters and their values:

• 🔋 Voltage: voltage: Normal: 3700-4200 mV at 100% charge. If below 3500 mV at 50%, the battery is worn out.
• 🌡️ Temperature (°C) Temperature. Optimal: 20-40°C. Above 45°C - overheating.
• ⚡ Capacity is a real capacity. Compare it to a passport (e.g., 5,000 mAh). >20%, it's time to change the battery.
• 📉 Health (%) - wear. 80% and below - critical wear.

How to check the wear of the battery:

1. Go to the service menu using the code ##4636##.
2. Select the Battery Information tab.
3. Compare Capacity to the rated capacity of your model (indicated on the box or in the specifications).

Example: on the Redmi Note 10 Pro passport capacity is 5020 mAh. If the menu shows 3800 mAh, wear is ~25%, and the battery should be replaced.

⚠️ Note: Some applications (e.g. AccuBattery) show battery wear, but their data is often overstated. The service menu gives accurate values because it reads data directly from the controller.

💡

If the Health setting is less than 70 percent and the phone is turned off at 20 to 30 percent charge, that's a sign of critical wear and tear, and delay battery replacement, and the risk of a sudden shutdown will increase.

Network and modem testing: how to improve signal

In Network Testing (or Radio Information), you can check the connection quality to the operator’s network, the strength of the signal, and even manually select bands if the automatic mode is not working well, which is useful if you have a weak 4G/5G signal.

How to check the strength of the signal:

1. In the service menu, select Network Testing.
2. Look at the parameters: 📶 Signal Strength (dBm) is optimal. -70 before -90 dBm. If below -100 — bondage. 📡 LTE/5G Band: shows the frequency used (e.g., band, B3 (1800 MHz)). 🔄 Ping (ms): delay. Normal: <50 miss.

If the signal is weak, try:

• 🔄 Manually select the network: Settings → SIM-maps and mobile networks → Choice of network → Manual scanning.
• 📡 Change your preferred network type: for example, forced LTE Only if 5G floundering.
• 📶 Use repeater (signal amplifier) or change operator.

Some models (such as Xiaomi 13 Pro) have 5G diagnostics available:

1. In the service menu, select 5G NR Testing.
2. Check the RSRP (signal) and SINR (quality) settings. Optimal: RSRP > -90 dBm SINR > 15 dB

⚠️ Note: Changing Band Selection settings without knowing the frequencies your operator supports can result in total network loss. B28 (700 MHz) and your carrier doesn’t use it, your phone won’t be able to connect to the internet.

Recovery after failure: reset and flashing

If the service menu changes, the device malfunctions (unplugged, no network, system errors), there are several ways to restore it, and it is important to proceed in order, starting with the safest methods.

Recovery methods:

1. Soft reboot: Hold the Power for 10 to 15 seconds. Helps with the freezes.
2. Reset via Recovery: Turn off your phone. Press Power + Volume Up before the Mi logo appears. Select Wipe Data → Wipe All Data (deletes all data!).
3. Fastboot Flash: Download the official firmware for your model from Xiaomi. Connect your phone to your PC in Fastboot mode (press Power + Volume Down). Use the Mi Flash Tool to install the firmware.