G925f Modem File U6 May 2026

After a failed custom ROM installation (LineageOS, Pixel Experience), the EFS partition (where the IMEI is stored) becomes corrupted. Users believe flashing a "U6" modem file will rebuild the IMEI. It will not. The modem file controls the radio; the EFS partition contains the unique ID. You need a backup, not a new modem.

1. NTN (Non-Terrestrial Networks) Readiness Parsing the NV items, I’m seeing direct references to NTN_SAT0 and NTN_SAT1. "U6" includes the physical layer drivers for Satellite SMS. Unlike the T-Mobile SpaceX thing, this appears to be integrated directly into the baseband firmware—no separate satellite chip. Expect emergency messaging via GEO satellites out of the box.

2. AI-RFFE (Radio Front End) Steering The U6 modem file is 18% larger than the S24’s U5 file. Why? Neural processing units (NPUs) embedded inside the modem firmware. The file contains weight matrices for predicting band congestion. The G925F will literally use on-modem AI to hop between 4G, 5G mmWave, and 6G (FR3) without waking the main CPU. This is huge for battery life during video calls. g925f modem file u6

3. The "Write Lock" Issue Warning: If you flash the raw G925F_U6_modem.bin onto a U5 bootloader (S24 series), you will hard brick your radio. The U6 file introduces a new Secure Write Toggle (SWT) . Samsung has locked the modemst1 and modemst2 partitions to only accept U6-signed binaries. Downgrading from U6 to U5 results in Baseband Unknown.

The SM-G925F uses Samsung’s Exynos 7420 (Shannon 333 / CMU500) with an Intel/Infineon-derived baseband.
Unlike Qualcomm devices (where modem firmware is NON-HLOS.bin), Samsung Exynos splits it into: After a failed custom ROM installation (LineageOS, Pixel

U6 refers to the 6th-generation bootloader – released around 2017 with Nougat.
The modem binary is tied to the bootloader version due to trustzone/RPMB changes.

If you only need to restore your modem and not hunt for a specific "U6" version, use Smart Switch’s "Emergency Software Recovery." It will flash the latest official modem for your device—likely U6 if that is the current revision. U6 refers to the 6th-generation bootloader – released

If you’re on U6 modem, you must be on U6 bootloader – else SW REV CHECK FAIL in ODIN.

modem.bin is device-specific – don’t flash G925F modem to G920F (even though both Exynos 7420). Differences:

You can dump live modem firmware (rooted device):

dd if=/dev/block/platform/15570000.ufs/by-name/RADIO of=/sdcard/modem_dump.bin

The dumped image is identical to modem.bin in the firmware package.