Enable DIAG Mode on OnePlus
Qualcomm DIAG activation for OnePlus OxygenOS devices. OnePlus supports public bootloader unlock which makes DIAG accessible with root. The engineering menu dialer code works on some models.
Last verified 2026-04-15 on OxygenOS 14 and 15
Method 1 : engineering menu (*#808#)
On some OnePlus firmware builds, dialing *#808# opens an engineering menu where you can switch USB composite to DIAG enabled. No root required when available.
- Open the phone dialer
- Enter
*#808# - Navigate to USB Settings
- Select DIAG composite mode
If the code is ignored, the menu was removed in your firmware. Use Method 2.
Method 2 : ADB with root
Prerequisites : unlocked bootloader (fastboot oem unlock), Magisk root, USB debugging enabled.
adb devices adb shell su setprop sys.usb.config diag,serial_smd,rmnet_bam,adb
Supported models
- OnePlus 9 / 9 Pro (Snapdragon 888)
- OnePlus 10 / 10 Pro / 10T (Snapdragon 8 Gen 1/+)
- OnePlus 11 (Snapdragon 8 Gen 2)
- OnePlus 12 (Snapdragon 8 Gen 3)
- OnePlus Nord 2T / 3 / 4 (Qualcomm variants)
- OnePlus Nord CE series Qualcomm
US carrier variants may be locked. International and Chinese versions are typically unlockable.
HiCellTek without DIAG
HiCellTek RF Monitor reads the serving cell metrics on any OnePlus Qualcomm device through the Android Telephony API. No bootloader unlock, no root, no OxygenOS modification.
Frequently asked questions
Is OnePlus unlockable?
Yes, OnePlus has historically supported public bootloader unlock via fastboot oem unlock. This has become more restrictive on recent models and some regional variants.
Does *#808# work on OxygenOS 15?
On some models yes, on others no. The engineering menu accessibility varies per firmware build. Use the ADB method as the reliable fallback.
What is the OxygenOS equivalent of Samsung *#0808#?
*#808# opens an engineering mode menu on some OnePlus firmware versions. The menu structure differs from Samsung but allows USB mode switching when exposed.
Can I unlock a carrier branded OnePlus?
US carrier branded OnePlus (T-Mobile, Verizon) are typically locked permanently. International and Chinese versions are unlockable.
Does the procedure survive OTA?
Bootloader unlock persists. Magisk root may require reinstall after OTA. setprop config resets and must be re run.
Which OnePlus models work?
OnePlus 9, 10, 11, 12, Nord series with Qualcomm. Verify the chipset in Settings > About phone.