Database Users

Device doesn't connect to PC

Hi everyone,
I see this is an issue that is being extensively talked about but after trying many solutions proposed by many users I am still out of luck, there is no way I can connect my device to a PC. USB debugging is on, USB config is set to MTP, USB drivers are installed.... but still, no luck, won't connect.
This means that I cannot even unlock the bootloader the official way since the phone goes undetected. I am on MIUI 7 Global Stable MALCNDE and I cannot upgrade to MIUI 8.... because if I reboot to stock recovery from Updater, the phone will reboot to a fancy diagram advising me to plug in a USB cable. Also, if I try to reboot to recovery by holding power/vol +, the phone boots in some terrifying recovery in chinese, with only four options that are translated. One of them is recovery and if I click on it.... I get that fancy looking diagram.
So please, any advice on this would be much appreciated.
Thanks.

Did you tried the official MiFlash app? http://api.bbs.miui.com/url/MiFlash

Asus Zenfone 3 ZE520KL - connect to QPST

Hello,
I would like to unlock Band 20 on my Tw Phone to be used in Europe.
THe Phone is successfully rooted and Superuser installed.
I have tried to connect my ZE520KL to PC with QPST and QXDM, because I would like to unlock the Band 20.
I have tried:
Device is rooted (follow this forum)
adb Shell / SU / setprop sys.usb.config diag,adb -> and confirmed the status is diag mode
Install Qualcomm USB driver (shown in Windows 10 Device Manager)
-> but QPST do not find any Phone or other USB device
Before this, I have also tried Signal Guru, which display Band 20, and I can lock it,
but the phone do not connect to any LTE band.
May I ask for any recommendations?
Is there any alternative way to unlock Band 20?
Thank you.

Take a look at this thread to start with.
I'm interested in this as well but haven't had any luck. From what I've read, it looks like its more than just nv values in 6828/6829 that block it from working, possibly hardware along with some other encrypted values that once you change seem to break all signal for the phone.

Hello, thankyou for the link.
I have tried it before without success.
Diag mode through adb works, but when i run the script to connect via the Qualcomm driver,
Adb closes (back to promt), but Qpst is still not finding any device.
Regarding Signal Guru: after root etc. I have installed signal guru, and the added Band 20, as it was not shown in original list. Now, when i lock phone to band 20 or lte only, the app tries to test but without any signal and then always immedeately switches to GSM back.
Any othe way i can try?

wang1chung said:
Take a look at this thread to start with.
I'm interested in this as well but haven't had any luck. From what I've read, it looks like its more than just nv values in 6828/6829 that block it from working, possibly hardware along with some other encrypted values that once you change seem to break all signal for the phone.
Click to expand...
Click to collapse
Hi Wang1Chung (Nihau
Did you try to install other custom rom, e.g. for Nougat (I am still using Marshmellow),
if this can help to solve to unlock Band 20?
I am still trying to connect my phone to QPST, one question here:
in the past, my Win10 Laptop detected the Zenfone3 as "other Device" and "USB Controller",
and today I installed one other driver (from Xiaomi Mi5) for Qualcomm, now the device manager
shows the phone at "Modems".
Does this mean, my Laptop sees the phone, and the driver works?
In this case I consider maybe by diag mode is not ok. -> How can I check diag mode is running?
I use ADB Shell with setprop, and in properties it shows "sys.usb.config diag,adb", therefore it should be in diag mode, right?
Is there any code I can put phone to diag mode (Just to verify it is not this issue)?
Thank you!

@Ser71MB1
I didn't try any other roms as there weren't many options when I tried.
I think Windows 10 is your issue. Try running Windows 7 32bit and force windows to use the driver that QPST can find that I mentioned in the previous thread. I think remember reading people had issues with getting QPST to work in windows 10.
From what I remember, with my phone plugged in to my computer, when I successfully enabled diag mode, my phone disconnected and then reconnected with a difference driver....is yours doing that?

Unknown USB Device (Device Descriptor Request Failed)

Hello guys,
after trying everything I could imagine and find on the net, I still didn't get my PC to recognize my S6 edge plus.
Hopefully someone od you has got some more ideas.
The Problem:
Connected Phone shows "Unknown USB Device (Device Descriptor Request Failed)" in the device manager. No MTP connection and no ADB possible so far.
Done so far:
Samsung USB Mobile Drivers
Kies
Smart Switch (with reinstall of drivers)
6 different cables with 4 PCs (2 Win10, 1 Win7, 1 Linux)
USB-Debugging on / off
*#0808# switched through every mode
USB-Hub drivers
Factory Reset
More Info:
5 of the 6 cables are working just fine for data connection with my S3
There is no infobar tooltip to change USB mode at all, just telling me it's loading
In Download Mode the phone doesn't get recognized by Odin (with same cord and USB Port the S3 does)
In Stock Recovery Sideload Mode the Device does not show up in adb devices (with same cord and USB Port the S3 does)
Regards

up

I'm guessing you have downloaded and installed the Samsung drivers?

New Infos on this case:
Local tech support inspected the phone. They suspect the mainboard to be defective due to corrosion signs.
Of course the repair cost would be ridiculous.
I'm gonna repair it myself, but I'm not quite sure if it's really a faulty mainboard.
I rather think of changing the USB board first, because it's like a 10th of the mainboard and more likely to get wet if that's the reason for the damaged phone.
Any ideas??
Regards

You didn't mention if it charges via USB?

Im in the same situation..
charge via usb but is not able to recognize the phone in any computer (a lot of different cables with 3 PCs)
My unit was wet and i think that something is wrong for this reason.

Hello friend my s6 edge plus demo with smokkierom last day not working ota,
I have activate developer mode for check control usb, but not have possibility for change other mode. Is fixed to mtp mode and not possible change other type.
I have deleted more app. And have chek update for play store.
I have press multiple tap and have activate developer mode to play store.
My idea is phone have one one virus....ajaj
I have reboot the phone with charger connected, and at reboot I have recevied FRP LOCK!!!!!!
Question one.... is possible recovery data?
A this time need connecting with Odin for upload twrp... but pc not find my phone!!
Working only charging.
And have error unknow devices. And not install driver..
Device not have USB ID and PID
My phone have hardware problem?
Best regards thank s help support

Fix
Cento50 said:
Hello friend my s6 edge plus demo with smokkierom last day not working ota,
I have activate developer mode for check control usb, but not have possibility for change other mode. Is fixed to mtp mode and not possible change other type.
I have deleted more app. And have chek update for play store.
I have press multiple tap and have activate developer mode to play store.
My idea is phone have one one virus....ajaj
I have reboot the phone with charger connected, and at reboot I have recevied FRP LOCK!!!!!!
Question one.... is possible recovery data?
A this time need connecting with Odin for upload twrp... but pc not find my phone!!
Working only charging.
And have error unknow devices. And not install driver..
Device not have USB ID and PID
My phone have hardware problem?
Best regards thank s help support
Click to expand...
Click to collapse

Cento50 said:
Fix
Click to expand...
Click to collapse
Hi Cento50. Have You managed to get the phone to work? At first my phone was showing up in "This PC" on Win 10. but after trying Samsung usb drivers to get Odin3 working now it is the same as Yours. Shows in Device Manager as: Unknown USB Device (Device Descriptor Request Failed). A strange Conundrum.

Hello @Photobil2012 yes fix habe worked!
One little wire have replaced 2ohm resistor.
And have fix fast charger and data comunication with PC!
We i have repaced first one diode.
Phone a this time work complete.
First this problem i have connected one hard disk to otg cable with phone battery low!
My suggestion Please caution to use otg interface with high current if have low battery in the phone.
This cause high current drain and possibile burn diode and resistor.

Hi Cento50,
Alright! Thank you very much for the most timely reply and tech info on the successful fix. This is very good news to receive. I just replaced the battery so it is brand new and that works fine now. However, if it is necessary I can apply the same type of fix that you applied. Great work, and thanks again for your help.

"USB connection mode" Greyed out

I purchased a Sony Xperia X Compact a while back and ever since the Oreo update the trouble began.
It drained the battery constantly and would not connect to any computer with any type of usb cable or adapters.
I contacted Sony and after 4 months of back and forth they told me that the phone is out of warranty and they cannot help.
I started looking into hardware issues, found not problems, replaced the phone port charger and battery (the battery was faulty and currently I'm waiting for another new one). While still using the old battery I did a factory reset, no help there.
I followed instruction on Sony website to unlock the phone and bootloader (worked with incomplete instructions) as I wanted to flash it, went through enabling developer options ... etc. Nothing I tried worked.
My plan is to install Nougat back or fix the Oreo and be able to connect to a computer using a USB anytime.
Two things I noticed in the phone:
Until last night, the bootloader was greyed out also, when I installed Quick Boot App. Now it magically became alive. It still wouldn't let me restart in fastboot mode and it says that request for superuser permission has been denied.
On another thread I read that if the bootloader is greyed out the bootloader is already unlocked. Is that correct?
The "USB Connectivity > USB connection mode" says "nothing connected" and I am literally connected to the computer as I type this.
I already tried many different cables, adapters and computers. Nothing worked.
Is there Any way to make things work for the USB and battery drain?

XT1687 - Device refuses to switch into DIAG mode.

Hello friends.
I have spent 2 days reading the forums and finally decided to post after not being able to get my XT1687 to switch into DIAG mod so that I can use QPST.
The device is boot loader unlocked, flashed with TWRP, running Arrow OS Pie.
No trick such as using setprop sys.usb.DM or Diag, or anything seems to work. Also, no dialer codes seems to work.
All I can manage to do with Shell is reset the USB connection.
No combination of Vol + UP or 3 finger "saluting"... while in bootloader on BP Tools, QCOM, Tools Mode (Switch to Enable) seems to work. I have tried with every setting of USB Configuration combined with debugging on, or debugging off. Nothing will prompt my Windows 10 machine to call for several of the version of the Qualcomm driver's that I have installed - and the only remotely close to a COM Port is when I set it to USB Tether and sets up as a network adapter but I have not been able to manually update that or any other driver so that it establishes a COM port.
Like, am I just stupid and this doesn't have Qualcomm hardware in it or something?
Very much appreciate any guidance.