10 Secret HyperOS & MIUI Dialer Codes Every Xiaomi User Must Know!

Did you know that your phone’s default Phone/Dialer app hides secret diagnostic menus, hidden battery stats, and hardware testing interfaces?

Whether you are buying a used Redmi/POCO phone in Bangladesh or want to test if your phone’s display, speaker, or battery health is performing correctly, these hidden *#*# dialer codes unlock advanced engineer menus built directly into HyperOS and MIUI.

Here are the 10 most useful secret dialer codes tested on Xiaomi, Redmi, and POCO devices.

1. The Ultimate Factory Test Menu (CIT Hardware Diagnostics)

• Secret Code: *#*#6484#*#* (or *#*#64663#*#*)
• What it does: Opens the Control Innovation and Transportation (CIT) engineer menu. This allows you to individually test every hardware component—including the touch screen digitizer, micro-vibration motor, proximity sensor, secondary microphone, and camera sensors—before buying a used device.

2. Detailed Battery Health & Charging Stats

• Secret Code: *#*#6485#*#*
• What it does: Displays exact battery charging cycles, current battery health state, temperature, and charging protocol.
  • Look for MF_02 (Total charging cycles completed).
  • Look for MB_06 (Battery health condition: “Good” means normal capacity).

3. Generate System Bug & Diagnostics Report

• Secret Code: *#*#284#*#*
• What it does: Immediately triggers a full system log backup. The generated bug report zip file is saved in your device storage (MIUI/debug-log/). Useful if your phone reboots randomly or experiences sudden performance drops.

4. Phone Information & Network Band Settings

• Secret Code: *#*#4636#*#*
• What it does: Opens the testing menu for SIM 1, SIM 2, and Wi-Fi status. You can force your network to NR Only (5G) or LTE Only (4G) to stop your phone from bouncing between weak 3G and 4G signals in low-reception areas in Bangladesh.

5. Enable/Disable VoLTE Carrier Check

• Secret Code: *#*#86583#*#*
• What it does: Toggles VoLTE carrier restrictions. If HD voice calls aren’t working on Grameenphone, Robi, Banglalink, or Teletalk, entering this code disables the default carrier check and forces VoLTE support on your device.

6. Enable/Disable VoWi-Fi (Wi-Fi Calling) Check

• Secret Code: *#*#869434#*#*
• What it does: Disables the carrier check for Wi-Fi Calling, revealing the hidden “Make calls using Wi-Fi” toggle under SIM Card Settings.

7. Instant IMEI Checker

• Secret Code: *#06#
• What it does: Displays your phone’s official IMEI numbers and Serial Number instantly. Essential for checking BTRC official registration status in Bangladesh before purchasing any device.

8. Enable/Disable 5G Carrier Check

• Secret Code: *#*#54638#*#*
• What it does: Toggles carrier-specific 5G network checks, allowing you to manually enable 5G Standalone (SA) or Non-Standalone (NSA) options on supported regional operators.

9. Turn On DC Dimming Option (Flicker Reduction)

• Secret Code: *#*#3223#*#*
• What it does: Activates the hidden DC Dimming menu on supported AMOLED displays, reducing screen flickering at low brightness levels to prevent eye strain during night use.

10. Thermal Throttle Test & Check

• Secret Code: *#*#76937#*#*
• What it does: Toggles hardware thermal throttling checks for testing high-load thermal efficiency during gaming sessions.