No LTE - Issues & Suggestions? Flash radio/modem?

[natenkiki2004]

XT1625 (regular G4) here and I've had a weird issue for a while. Got the phone back in February, did a warranty claim a couple months ago for this and another issue. Ever since I got the first phone, continuing onto the replacement, I've never had consistent LTE. The only time I seemed to get it was on the replacement phone right out of the box. Restarted and it disappeared until the next Android update where LTE would appear on the first boot and disappear if I restarted, until the next update. I could get LTE to work and verify proper speeds, then restart and it's back to HSPAP until a wipe or Android update. I made a crappy video about it here: https://www.youtube.com/watch?v=TYl5-Jn8rmU

Yesterday, I got an urge to install LineageOS in hopes that the issue would be permanently fixed on there. Nope. Still no LTE, only HSPAP even after messing with APN settings and radio settings in the service menu. It was a long process and I was busy but I don't think I had LTE on first boot oddly enough.

Also yesterday I fixed a spare G2 that had been having issues receiving MMS and getting Data for weeks (while calls and SMS worked fine), an issue that came up out of nowhere. Contacted provider multiple times, no issue there. Wipe phone, still same issue. Finally had the eureka idea and re-flashed/wiped the bootloader and modem. Data and MMS came back! I bring this up because I'm wondering if maybe my G4 needs the same thing done? It's not a provider issue because LTE does work under certain circumstances and I've called them countless times about it. Not an APN issue because those settings don't change on restart.

Anyone got any ideas? Is this issue seen on other people's phones? Is there a collection of radios/modems/basebands that I can download and flash? I did find a thread with them but they had been removed.

 

[strongst]

Anyone got any ideas? Is this issue seen on other people's phones? Is there a collection of radios/modems/basebands that I can download and flash? I did find a thread with them but they had been removed.

You can flash the modem always seperately with the command

fastboot flash modem NON-HLOS.bin

From here: https://forum.xda-developers.com/moto-g4-plus/how-to/stock-rom-npjs25-93-14-4-march-1-t3608138

But make sure you have at least nougat firmware! If not, it's better to flash the whole rom but it will wipe everything on your device.

 

[natenkiki2004]

You can flash the modem always seperately with the command

fastboot flash modem NON-HLOS.bin

From here: https://forum.xda-developers.com/moto-g4-plus/how-to/stock-rom-npjs25-93-14-4-march-1-t3608138

But make sure you have at least nougat firmware! If not, it's better to flash the whole rom but it will wipe everything on your device.

YES!!!! THANK YOU!!!!

LTE is now working, even after rebooting. I downloaded that stock ROM file and pulled out fsg.mbn and NON-HLOS.bin then booted into fastboot and entered the following commands:

fastboot flash modem NON-HLOS.bin
fastboot erase modemst1 
fastboot erase modemst2
fastboot flash fsg fsg.mbn

I genuinely do not understand how I got 2 factory phones and neither would stick to LTE out of the box. Also odd that installing LineageOS clean didn't work to flash those particular files. Just like the G 2014 model that required just about the same commands to get GPS working again.

Thanks again!

 

[natenkiki2004]

I also want to note that I used this same process to fix data on a Moto G 2014 variant and a Moto E LTE variant. I am doing this again because the G 2014 seems to have lost data again. I wonder if Motorola has issues with it's software corrupting over time or if the chips in these devices share something in common.