How To Open Fastboot Mode On Oppo A37 Verified

Before diving into the steps, let's clarify why you're here.

However, you can still prepare the device for modifications by using the official Oppo Bootloader Unlock Tool and a special key combination.

This is the closest you will get to a "Fastboot Mode" on the Oppo A37. This method does not display "FASTBOOT" on the screen but places the device in a state where your PC can communicate with it to unlock the bootloader via Oppo's official tool.

Fastboot mode is a low-level Android bootloader interface used for flashing firmware, unlocking bootloaders, and running device-level commands. On the Oppo A37 (also sold as A37f/A37fw), entering fastboot lets advanced users perform tasks like flashing images or unlocking the bootloader. Follow these verified, step-by-step instructions and safety notes.

adb reboot bootloader

One unique aspect of the Oppo A37 that deserves a mention in this review is the "Fastboot Mode... Press Power Key to Exit" loop.

On many newer phones, you can exit Fastboot simply by holding the power button again. On the A37, if you enter Fastboot and do nothing, the phone will stay there until the battery dies or you force a restart. However, some units have a bug where the Power button press to exit does not register immediately.

User Experience Tip: If you are stuck in Fastboot and cannot exit, hold the Power button for 15+ seconds until the screen goes black and the phone reboots. This is a "hard reset" of the session and is often the only way out if the software is unresponsive.

If your phone boots normally and you have USB Debugging enabled: Before diving into the steps, let's clarify why you're here

What you will see: The screen will enter Oppo's Engineering Mode / Download Mode. It will look like a black screen with small white text showing options like:

If you see "Reboot to Bootloader": Select it using the Volume keys and press Power to confirm. This will often just reboot normally. If so, proceed to Method 2.

This guide should help you access Fastboot mode on your Oppo A37. If you encounter issues, double-check each step and verify that your device and computer can communicate properly via ADB.

To enter Fastboot mode on your OPPO A37, use the following verified hardware button combination or the software-based ADB method.  Method 1: Hardware Button Combination 

This is the standard way to enter Fastboot mode when the device is powered off. 

Power Off: Press and hold the Power button for a few seconds to completely turn off the device. However, you can still prepare the device for

Key Combo: Simultaneously press and hold the Volume Up + Power button for several seconds.

Release: When the Fastboot Mode screen or text appears on the display, let go of all buttons.

Verification: You should now see a black screen with "Fastboot" text, indicating you are in the correct mode.  Method 2: Via ADB (PC Required) 

If your physical buttons are not working correctly, you can use a computer to trigger the mode. 

Enable Debugging: Go to Settings > About Phone and tap Build Number 7 times to enable Developer Options. Then, go to Additional Settings > Developer Options and turn on USB Debugging.

Connect to PC: Connect your OPPO A37 to a computer using a stable USB cable.

Run Command: Open a command prompt or terminal in your ADB folder and type:adb reboot bootloader The phone will automatically restart into Fastboot mode.  How to Exit Fastboot Mode 

To return to normal operation, press and hold the Power button for about 10–15 seconds until the device vibrates and restarts normally. Alternatively, if you are using a PC, you can enter the command fastboot reboot.