How to Tell If a Samsung Phone Has Triggered Knox Warranty Void (Fuse Burn): Detailed Explanation and Detection Guide

When using a Samsung phone, you may have heard of the term Knox Warranty Void (commonly called Knox fuse burn).
It is triggered when the system detects that the device has been modified or subjected to improper operations, which may affect certain security features.
Many users worry that once Knox is tripped, some key functions on their phone may permanently stop working.

This article explains what Knox fuse burn is, how to check your phone’s Knox status, and how FRP Lock and OEM Lock relate to Knox, helping you better understand and protect your Samsung device.

 What Is Knox Fuse Burn?

Knox is Samsung’s built-in security platform, officially known as the Samsung Knox Security Platform.
At the hardware level, it uses an eFuse mechanism to record the security state of the device.

• When the system detects an unauthorized modification or irregular operation,
  the eFuse will be permanently tripped (fused)and cannot be reset.
• Even if you reinstall official firmware later, the Knox status will not revert to normal.

This means:

Once Knox is tripped, certain Samsung security features—such as Samsung Pay, Secure Folder, and data encryption—will be permanently disabled.

 How to Check If Knox Has Been Tripped

The most reliable way to verify Knox status is through Download Mode:

 Method: Check via Download Mode

1. Power off your phone.
2. Press and hold Volume Down + Power(some models may also require the Bixby button) to enter Download Mode.
3. On the screen, you will see system information. Look for the line:

4. Knox Warranty Void: 0x0 or 0x1
   • 0x0→ Not tripped, Knox is intact.
   • 0x1→ Tripped, Knox permanently voided.

This is the official and most accurate way to check the Knox status on Samsung devices.

 Understanding FRP Lock and OEM Lock Status

In the same Download Mode or status screen, you’ll often see FRP Lock and OEM Lock listed together with Knox.
These indicators also reflect the phone’s overall security state, though they serve different purposes:

• FRP Lock (Factory Reset Protection)

• Indicates whether Google account protection is enabled.
• Purpose:Prevents the device from being used after a factory reset without verifying the original Google account.
• Relation to Knox:Independent from Knox; it does not trigger a Knox fuse burn.
  • OEM Lock (Bootloader Lock Status)
• Indicates whether the Bootloader is locked.
• Purpose:Prevents unauthorized modifications to the system.
• Relation to Knox:Unlocking the Bootloader is one of the most common causes of a Knox fuse burn.

By checking Knox Warranty, FRP Lock, and OEM Lock together, you can quickly understand your phone’s security status and determine whether any risky operations have occurred.

 Effects of Knox Fuse Burn

Once Knox has been tripped, the following functions may be permanently restricted or disabled:

• Samsung Payand Secure Folder become unavailable
• Samsung Healthmay no longer record sensitive data
• Official warranty coverage may be considered void(depending on regional policies)
• Enterprise security features such as Knox Workspacewill no longer be accessible

 Recommendations and Summary

• If you plan to modify system settings or perform advanced operations, understand the risks — Knox fuse burn is irreversible.
• Keeping the phone’s system in official, unmodified condition ensures all Samsung security features work properly.
• For most users, avoiding unnecessary system modifications is the best way to protect both device and data security.

In short:

Knox fuse burn is not a software glitch but a hardware-level security mechanism — once triggered, it cannot be undone.