Wrong model bootloader installed

[Headcase_Fargone]

Hi all,

I just picked up a refurbished AT&T Galaxy S3 (i747) and it appears to have the T-Mobile (T999) bootloader for some reason.

Here's what I've found model and version-wise...

System settings - About device:
Model number SGH-I747
Android version 4.1.2 (stock Touchwiz)
Build number I747ZSEMC1

Info app from Play store:
Boot loader version T999UVDMD5
Finger print samsung/d2vl/d2can:4.1.1/JRO03l/I747ZSEMC:user/release-keys
Product d2vl
Model SGH-I747

Download Mode shows T999 bootloader.

Putting a T-Mobile sim in registers on the network and for some reason I get H+, which I didn't think was possible with the I747 AT&T model. Don't have an AT&T sim to test with at the moment.

I've tried flashing the I747 4.1.2 bootloader but I get different error messages depending on which recovery I use to flash it.

Stock recovery:

Verifying update package...
E:signature verification failed
Installation aborted

Clockworkmod:

E:Error in (file path and name)
(Status 7)
Installation aborted.

TWRP:

E:Error executing updater binary in zip (file path and name)
Updating partition details...
Failed

My primary concern right now is how can I fix this bootloader issue so I can get a more recent rom like AOKP 4.4 on it? Any suggestions?

 

[srkmagnus]

The bootloader is something that needs to be flashed to the device. I'm pretty sure you can do it with Samsung devices, but risk ending up with a brick if something goes wrong. I would suggest contacting the seller to make sure the device was intended to be an att device. If it was modified then perhaps the seller can point you in the right direction to install the correct bootloader. You'll likely need to visit xda for the bootloader files.

Sent from my Nexus 5 using AC Forums mobile app

 

[Rukbat]

1747 (the first character is the digit "one") is a TMobile device. I747 (the first character is the first personal pronoun, pronounced "eye") is an AT&T device. You may just be misreading the character.

 

[Headcase_Fargone]

It's definitely the letter I, I just double checked. Also, it has an AT&T logo on it...

 

[Tyler Cleveland]

If the phone has an ATT based custom ROM on it, the build.prop will make it report it being an att device. As long as it works, dont worry. The two phones are almost identical as far as I know besides software, so the bootloaders are probably cross-compatible. At least one way. Check the radio/baseband version and see what that says. T-Mobile model number is sght999 BTW. Also check the boot loader lock status and the system write protection status.