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Press and hold down the physical button (on some specific devices, it may be Volume Up or both volume keys simultaneously).
Press and hold the primary boot key. For most Unisoc/SPD devices, this is ; on specific feature phones or tablets, it may be Volume Up or a central keypad button.
is a specialized state in Spreadtrum devices where the device USB port acts as a diagnostic interface rather than just a storage (MTP) or ADB interface. enter diag mode spd
: Use a high-quality data cable; some "charging-only" cables will fail to trigger the handshake. Are you trying to perform a specific repair like IMEI writing network unlocking , or do you just need to check the hardware logs
: Ensure you have the latest SPD/Unisoc USB Drivers installed. Without these, the "Diag" port will appear as an "Unknown Device" in Windows.
Open a Command Prompt on your computer and verify your connection via terminal: adb devices Use code with caution. Execute the factory test command structure: adb reboot ftm Use code with caution. : Press and hold down the physical button
Choose > Advanced Options > Startup Settings > Restart .
Accessing Diag Mode is a powerful capability for repairing and servicing Android phones with SPD/Unisoc processors. While there are several potential methods, the most consistent and effective approach is using professional software tools on a PC. By following the detailed steps and troubleshooting advice in this guide, you'll be well-equipped to handle this advanced repair technique.
: Fixes "Invalid IMEI" or "Null IMEI" errors caused by flashing bad firmware. is a specialized state in Spreadtrum devices where
Diag Mode SPD, also known as Diagnostic Mode SPD, is a special mode that allows device manufacturers, technicians, and advanced users to access and test various components of a device. SPD stands for Spreadtrum, a Chinese fabless semiconductor company that produces chipsets, processors, and other essential components for mobile devices.
Look at the Windows Device Manager under the section. You should quickly see SPRD U2S Diag (COMX) blink onto the screen. Note: In raw preloader mode, this port may only remain active for a few seconds before switching into battery charging mode unless a tool actively catches the connection. Method 2: ADB Shell Command (For Rooted Android Devices)
This article explains what the Spreadtrum Diagnostic Mode is, how to enter it, and the potential risks involved in using these tools. What is SPD Diagnostic Mode (Diag Mode)?