In short: I have a Xiaomi Mi4c that shows has an "unknown" IMEI when checked via the settings in the stable and developer versions of MIUI and Cyanogenmod 13.1. However, when viewed through EFS professional or NV RF Manager, the IMEI is read correctly. Not having a "valid" (or any?) IMEI means I have a 5" wifi tablet, rather than a phone, which is something I've been trying to fix.
The long version:
The problems started right after I flashed CM 13.1, and I couldn't detect my sim card. Thinking it was my ROM, I reflashed my stock ROM and when that didn't solve the problem, I quickly deduced that the missing/unknown IMEI was the problem.
I finally got NV RF Manager working, and read all of the NV values from my phone. After finding the IMEI related value, I followed the odd schema for rearranging my IMEI and filled the boxes out and clicked "Write NV." However, I only received an error that read "Parameter is write-protected and thus read only." The same results were achieved with EFS professional. (Again, this was on CM) Now, I reflashed the stock ROM, and tried again. After rebooting the phone, I was able to read the correct IMEI values from the phone using both EFS professinoal and NV RF Manager, but the phone still showed baseband and IMEI as "unknown." Dialing *#06# causes the numbers to disappear, but nothing else happens.
So far, this is what I've tried:
- NV RF Manager
- EFS Professional
- MTK Droid Tools
- SP Flash Tools (Did not work at all, only for MTK chipsets?)
- Apps like XPOSED IMEI Changer (Results in nothing changing)
There are a few related questions, but none of them work for me.
Might work, but I have been unable to find the "modem" or nvram files on my phone. I also don't have an "efs" folder on my phone (that I can find.)
Isn't jiving with me. The thought of uploading mi4i (rather than mi4c) specific files after removing my only remanents of my efs files seems like a bad idea to me.
Is ROM specific, and since it doesn't work on multiple ROMs, I've ruled it out as related.
Again I have a Xiaomi Mi4C, the 32GB/3GB version with the Qualcomm MSM8992 Snapdragon 808 chipset.
Any help at all would be greatly appreciated, I've hit a wall fixing this problem.