Need Help Restoring A2017U to Stock/Locking Bootloader/So it'll Accept OTA's

[dmw_4814]

O.K., I'm getting pretty desperate - I have an Axon 7 (A2017U) that I need to sell by, like, this weekend, and I'm having trouble restoring it to stock. Well, actually, I guess I'm having trouble now figuring out how to relock the bootloader, as I've got Nougat on there, and have apparently lost the ability to execute fastboot/ADB commands.

Here's exactly what's happened, so far:

1. I bought the phone; unlocked the bootloader (by downgrading from MM B27 to MM B20), and when I was done, ended up with an A2017U that had an unlocked bootloader on it; was rooted with TWRP, and had MM B29. All was cool.

2. Until I used it for about 8 or 9 days. I'm a tractor-trailer driver, and I keep all my music on my phone, so I can plug the phone into my truck's stereo & listen to it while I drive. About 8 or 9 days was all I could take of the Axon 7's distorted speaker/auxiliary jack output (sounds like gain is turned up to 11, on a scale of 1-10!). So, I bought a refurbished (looked completely brand-new, honestly) Moto X Pure Edition (2015). I HATE the current trend of taller/narrower phones, plus I need/want something that Xposed works on.

3. Since I'm gone away from home for weeks at a time, I missed the 30 day return window at Newegg, where I originally purchased the phone, and so now I need to sell it.

4. I flashed three files, via TWRP, in an effort to return to stock; A2017UV1.10B32_bootstack_by_DrakenFX.zip; A2017UV1.10B32_StockSystem_by_DrakenFX.zip, and finally A2017UV1.10B32_StockRecovery_by_DerakenFX.zip. This left me with a device that boots into Nougat, but I can't seem to figure out now how to relock the bootloader. I need to get rid of that unlocked bootloader warning screen. If I press the power key while that screen is displayed, the little (Linux) penguin appears. After 5 or 10 seconds, it goes away, and the phone boots into Nougat. I can get into the stock recovery, and I can get ADB to recognize the phone, when ADB or the Axon 7 Tools program tries to reboot the phone into EDL mode, ADB & fastboot report no devices are connected (adb reboot edl does nothing, except turn the phone screen black, and then ADB reports no devices are connected)

How do I go about returning this thing completely stock, so that I can sell it, and any potential buyer hasn't a clue I unlocked the bootloader/rooted it, and it gets OTA updates, just like when new? FYI; I don't care if it has MM B27 (what it had when I took it out of the box); MM B29, or Nougat B32 (what it's got now) - I just want it to be stock, with a locked bootloader, and the ability to receive/take OTA's.

I quit my job today, because I just wasn't getting enough miles at my employer to make enough money, and I'm starting a new (driving) job on Monday. Orientation is in Oklahoma City, OK, and I have very little cash on hand, at the moment, so I need to get this phone set up and listed on Craigslist, like, tomorrow! Any help anyone can give me would by greatly appreciated by me!

Thanks!

Dennis

 

[lafester]

Use the toolkit

 

[Choose an username...]

O.K., I'm getting pretty desperate - I have an Axon 7 (A2017U) that I need to sell by, like, this weekend, and I'm having trouble restoring it to stock. Well, actually, I guess I'm having trouble now figuring out how to relock the bootloader, as I've got Nougat on there, and have apparently lost the ability to execute fastboot/ADB commands.

Here's exactly what's happened, so far:

1. I bought the phone; unlocked the bootloader (by downgrading from MM B27 to MM B20), and when I was done, ended up with an A2017U that had an unlocked bootloader on it; was rooted with TWRP, and had MM B29. All was cool.

2. Until I used it for about 8 or 9 days. I'm a tractor-trailer driver, and I keep all my music on my phone, so I can plug the phone into my truck's stereo & listen to it while I drive. About 8 or 9 days was all I could take of the Axon 7's distorted speaker/auxiliary jack output (sounds like gain is turned up to 11, on a scale of 1-10!). So, I bought a refurbished (looked completely brand-new, honestly) Moto X Pure Edition (2015). I HATE the current trend of taller/narrower phones, plus I need/want something that Xposed works on.

3. Since I'm gone away from home for weeks at a time, I missed the 30 day return window at Newegg, where I originally purchased the phone, and so now I need to sell it.

4. I flashed three files, via TWRP, in an effort to return to stock; A2017UV1.10B32_bootstack_by_DrakenFX.zip; A2017UV1.10B32_StockSystem_by_DrakenFX.zip, and finally A2017UV1.10B32_StockRecovery_by_DerakenFX.zip. This left me with a device that boots into Nougat, but I can't seem to figure out now how to relock the bootloader. I need to get rid of that unlocked bootloader warning screen. If I press the power key while that screen is displayed, the little (Linux) penguin appears. After 5 or 10 seconds, it goes away, and the phone boots into Nougat. I can get into the stock recovery, and I can get ADB to recognize the phone, when ADB or the Axon 7 Tools program tries to reboot the phone into EDL mode, ADB & fastboot report no devices are connected (adb reboot edl does nothing, except turn the phone screen black, and then ADB reports no devices are connected)

How do I go about returning this thing completely stock, so that I can sell it, and any potential buyer hasn't a clue I unlocked the bootloader/rooted it, and it gets OTA updates, just like when new? FYI; I don't care if it has MM B27 (what it had when I took it out of the box); MM B29, or Nougat B32 (what it's got now) - I just want it to be stock, with a locked bootloader, and the ability to receive/take OTA's.

I quit my job today, because I just wasn't getting enough miles at my employer to make enough money, and I'm starting a new (driving) job on Monday. Orientation is in Oklahoma City, OK, and I have very little cash on hand, at the moment, so I need to get this phone set up and listed on Craigslist, like, tomorrow! Any help anyone can give me would by greatly appreciated by me!

Thanks!

Dennis

Just one question - Did you try stuff, like Viper4Android, or using the Qualcomm DAC? maybe you could've ended up using the QC DAC and avoided having to buy an older phone and having to sell this one...

Or you could've tried custom ROMs which use a different driver and stuff.

I'm saying this because the AKM DAC has far different output than the Qualcomm one. I've read that it has like 80 Ohm internally, which would mean that it uses a bunch of voltage. while the Qualcomm one has less than 10 AFAIK. Not a real difference when using headphones (Even 32 Ohm 'phones don't really make any of the two sound louder than the other) but everyone says that one is much louder on lower impedances like 16 Ohm or less.

to try this, you can go to Sound, and put it on Standard mode. Or use the QS tile on MiFavor 5.0



But it seems like you just wanna get rid of it. If that's the case, you can use the toolkit like the guy above me said. There are guides also, but I think the toolkit works too. If you relock and you have tge stock recovery and the phone doesn't DFU brick or whatever, it will get OTAs. But I recommend you to download the latest A2017U Nougat MiFlash folder and flash it via miflash to make it completely stock before attempting to lock it.

 

[dmw_4814]

Use the toolkit

Tried that - no joy.

When I try to flash back to stock, I'm given two options - B15 N & B19 N. I choose B19 N, and it downloaded to my PC last night. It fails every time when I try to flash it. It tells me that EDL device is connected, launches MiFlash, and when I paste the directory to the file I'm trying to flash, then press flash, I'm invariably greeted with errors, mostly about "cannot read hello packet"; "trying to reset status", and finally I get an error, with the statement, "Object reference not set to an instance of an object".

Any further suggestions?

 

[dmw_4814]

Just one question - Did you try stuff, like Viper4Android, or using the Qualcomm DAC? maybe you could've ended up using the QC DAC and avoided having to buy an older phone and having to sell this one...

Or you could've tried custom ROMs which use a different driver and stuff.

I'm saying this because the AKM DAC has far different output than the Qualcomm one. I've read that it has like 80 Ohm internally, which would mean that it uses a bunch of voltage. while the Qualcomm one has less than 10 AFAIK. Not a real difference when using headphones (Even 32 Ohm 'phones don't really make any of the two sound louder than the other) but everyone says that one is much louder on lower impedances like 16 Ohm or less.

to try this, you can go to Sound, and put it on Standard mode. Or use the QS tile on MiFavor 5.0



But it seems like you just wanna get rid of it. If that's the case, you can use the toolkit like the guy above me said. There are guides also, but I think the toolkit works too. If you relock and you have tge stock recovery and the phone doesn't DFU brick or whatever, it will get OTAs. But I recommend you to download the latest A2017U Nougat MiFlash folder and flash it via miflash to make it completely stock before attempting to lock it.

I'm not exactly sure what you mean by "Qualcomm DAC" - what is that?

No, I don't necessarily WANT to get rid of the phone - I still actually have a few days left during which time I can request a return/refund from Amazon for the Moto X Pure Edition - but it kind of now would benefit me more if I can sell the Axon 7 in the next day or two, rather than wait 5 or 6 days for a refund from Amazon.

I generally prefer stock ROMs on my phones, as opposed to heavily customized ones. I know those other ROMs sometimes work better, but I'm just kind of "anal" like that, LOL!

 

[dmw_4814]

These are the errors I get in MiFlash, through the tookit:

[0.00 COM4]:[COM4]:start flash.
[2.01 COM4]:cannot receive hello packet,MiFlash is trying to reset status!
[4.52 COM4]:cannot receive hello packet,MiFlash is trying to reset status!
[7.02 COM4]:try to reset status.
[7.04 COM4]: object reference not set to an instance of an object.

 

[dmw_4814]

I got it sorted out. I reflashed TWRP onto the device, then flashed this "A2017UV1.0.0B29_RollBackModded.zip" from here: https://forum.xda-developers.com/axon-7/development/rom-guide-updates-to-stock-files-via-t3469484.

After doing that, I was able to relock the bootloader, so all appears normal/stock, now. I'm on MM B29, now.

Thanks to anyone who chimed in here with suggestions.

Dennis

 

[Choose an username...]

I'm not exactly sure what you mean by "Qualcomm DAC" - what is that?

No, I don't necessarily WANT to get rid of the phone - I still actually have a few days left during which time I can request a return/refund from Amazon for the Moto X Pure Edition - but it kind of now would benefit me more if I can sell the Axon 7 in the next day or two, rather than wait 5 or 6 days for a refund from Amazon.

I generally prefer stock ROMs on my phones, as opposed to heavily customized ones. I know those other ROMs sometimes work better, but I'm just kind of "anal" like that, LOL!

Look, normal phones have a DAC integrated on the CPU itself, somewhere on the CPU die. a DAC is a digital to analog converter is a thingy that converts digital signals (8-bit or 10-bit) to analog signals (volts, amps) and therefore needs to have very low noise and stuff. The DAC embedded on the CPU has a bunch of noise so the current trend is to add an additional DAC on another package, somewhere on the SoC. In this case this DAC is an AKM AK4xxx. This one is very good for high-end headphones, but not for some other stuff.
I assume your phone doesn't work? If it does, put the sound mode on Standard, and try it. if not I can help some xd

 

[dmw_4814]

Look, normal phones have a DAC integrated on the CPU itself, somewhere on the CPU die. a DAC is a digital to analog converter is a thingy that converts digital signals (8-bit or 10-bit) to analog signals (volts, amps) and therefore needs to have very low noise and stuff. The DAC embedded on the CPU has a bunch of noise so the current trend is to add an additional DAC on another package, somewhere on the SoC. In this case this DAC is an AKM AK4xxx. This one is very good for high-end headphones, but not for some other stuff.
I assume your phone doesn't work? If it does, put the sound mode on Standard, and try it. if not I can help some xd

LOL; yeah, I know what a DAC is - I'm pretty into audio stuff, and have been for many, many years. I just wasn't sure if you were talking about a setting on the phone somewhere, or some app to utilize a Qualcomm DAC, instead of whatever the phone was defaulting to.

In any case, since I've got the ROM issue sorted out (returned to stock), I think I'm just going to go ahead and list the phone on Craigslist; see if anyone local is interested in it. Thanks.

 

[Choose an username...]

LOL; yeah, I know what a DAC is - I'm pretty into audio stuff, and have been for many, many years. I just wasn't sure if you were talking about a setting on the phone somewhere, or some app to utilize a Qualcomm DAC, instead of whatever the phone was defaulting to.

In any case, since I've got the ROM issue sorted out (returned to stock), I think I'm just going to go ahead and list the phone on Craigslist; see if anyone local is interested in it. Thanks.

Okay then lol

I'd try the other DAC first but it seems like you wanna get rid of it anyways