# [Q] Why the MTK 6589 USB Vcom port disapear after 2 second?



## Sohan_Saymum (Mar 8, 2014)

I am trying to upgrade my Canvas HD 20 Android 4.2.1. But, everytime I connect the phone with my pc, the "MTK6589 USB Vcom port" appears for only 2 second in the device manager, then it's gone. And the "Device Disconnect Sound" is played. So, I cant flash the ROM. what's going wrong? I have followed every steps in this tutorial. 
http://forum.xda-developers.com/showthread.php?t=2308431

.....
I have Tried in different PCs and with different Data Cables. But same problem exists. And, I had no problem with this cable while sharing files with my pc. I used this cable for Mass Storage.
I figured that, the connection problem I have described previously is the main cause of this mess. can anyone help me out with this?????


----------



## touji (Apr 12, 2014)

Sohan_Saymum said:


> I am trying to upgrade my Canvas HD 20 Android 4.2.1. But, everytime I connect the phone with my pc, the "MTK6589 USB Vcom port" appears for only 2 second in the device manager, then it's gone. And the "Device Disconnect Sound" is played. So, I cant flash the ROM. what's going wrong? I have followed every steps in this tutorial.
> http://forum.xda-developers.com/showthread.php?t=2308431
> 
> .....
> ...

Click to collapse



have you tried put the battery inside and after that plugin to usb for flashtool to detect, because my phone is not detected in flashtool if its without battery inside


----------



## MT6589 (Jun 20, 2014)

*MTK6589 connects and disconnects continuously*



touji said:


> have you tried put the battery inside and after that plugin to usb for flashtool to detect, because my phone is not detected in flashtool if its without battery inside

Click to collapse



I have same problem.


----------



## Jarmezrocks (Oct 1, 2014)

Did anyone get a solution to this issue? I am totally stumped and not sure how to revive this device when there is no obvious solution to the driver fault. People seem to pretend that this issue doesn't exist or that users are doing things incorrect....I am following instructions to a T and still I get the driver dropout issue. This is SOOOO frustrating. It connects and detects, then before I can do anything it disconnects. What freakin drivers work for the MTK6589? I was told that all MTK devices use the same drivers....well I have tried literally 15-20 different driver downloads and NONE of them work! NONE! They ALL have the same issue of connect and then disconnect. Yes I have USB debugging enabled. Yes I have tried battery out and then battery in. I have tried everything and nothing has worked. Please if anyone can help me with drivers that work I would very very very much appreciate.....otherwise this devices is pretty much a brick (I am a long time Android user not a n00b btw).
For reference....the device came to me to be translated to English from Chinese. I did this mostly but made a mistake with one line in the build.prop. Now it won't boot. There is no custom recovery available for this device so I have no other option but to reflash the device.....IF only I could get it to detect for more that 2 freaking seconds I would try with the backup I made before modifying the thing!


----------



## niki_help (Oct 27, 2014)

*MTK 6589 VCOM port disconnecting*

Hello,
I have the same problem. I did everything discribed in forums. The driver of MT Preloader Vcom port is installed correctly.  I tested with different cables and different OS (XP and Windows 7 32 bit) and differenet computers.... SP Flash Tool says that:
BROM ERROR : S_BROM_DOWNLOAD_DA_FAIL (2004)
[H/W] Fail to download DA to baseband chip's internal SRAM
[HINT]: 1. There's an cable communication problem between FlashTool and BootROM.
2. Target might be shutdown unexpectedly or target lost power supply.
[ACTION] 
1. Try again. 
2. Proceed H/W checking in download cable and target side com port. 
3. Monitor if power-drop occured in target side. 
At some reason COM port is constantly disconnecting and connecting without establishing permanent connection with SP Flash Tool. The red bar pops up and shows that message on hitting download  button on the Flash Tool.

Any idea?


----------



## niki_help (Oct 31, 2014)

*MTK 6589 connect/disconnect*



Jarmezrocks said:


> Did anyone get a solution to this issue? I am totally stumped and not sure how to revive this device when there is no obvious solution to the driver fault. People seem to pretend that this issue doesn't exist or that users are doing things incorrect....I am following instructions to a T and still I get the driver dropout issue. This is SOOOO frustrating. It connects and detects, then before I can do anything it disconnects. What freakin drivers work for the MTK6589? I was told that all MTK devices use the same drivers....well I have tried literally 15-20 different driver downloads and NONE of them work! NONE! They ALL have the same issue of connect and then disconnect. Yes I have USB debugging enabled. Yes I have tried battery out and then battery in. I have tried everything and nothing has worked. Please if anyone can help me with drivers that work I would very very very much appreciate.....otherwise this devices is pretty much a brick (I am a long time Android user not a n00b btw).
> For reference....the device came to me to be translated to English from Chinese. I did this mostly but made a mistake with one line in the build.prop. Now it won't boot. There is no custom recovery available for this device so I have no other option but to reflash the device.....IF only I could get it to detect for more that 2 freaking seconds I would try with the backup I made before modifying the thing!

Click to collapse



Hello,
The connecting and disconnecting is normal for MTK devices in Device Manager. You don't have to panic. All you need is to be very fast when you see in your computer - Device Manager - MTK Preloader - click with right button - properties - driver - update driver - choose from specific location - next - browse for the file and then install the driver from the directory where you have put it.  You have to see Windows Message that your driver is not digitally signed and press Continue.
Don't pay attention that MTK is connecting and disconnecting.  When you install the driver it must be shown up(and of course disappear in 2 seconds) in LPT ports - MTEK VCOM Port or something like that. You are ready.
If you have installed a bunch of different drivers use the program USBdeview (goolge it)and unistall all MTK Preload drivers you have already installed.
Then you are ready to flash backup files with SP Flash Tool.


----------



## Jarmezrocks (Nov 12, 2014)

Hey guys,

Guess what?! I FOUND THE ANSWER!!! The disconnect is by design. The device is not actually meant to stay connected. I will explain why later but first I will direct you towards the correct information to get you back up and running again.

Follow this guide step by step BUT READ EVERY STEP EVER SO CAREFULLY.... also take note of the points below that I am going to emphasise that AREN'T emphasised anywhere in any other tutorials I have followed
http://forum.xda-developers.com/showthread.php?t=1982587

The part that is not emphasised is this


> Turn off your phone, remove the battery* and replace it after some seconds* (and don't turn on the phone).
> *Press F9 (or hit Download button) and connect your phone* into the computer via USB data cable.
> The process will start and a red progress bar will appear.

Click to collapse



In both cases the word 'and' should be replaced with the word 'THEN' so that people will understand.

What isn't really mentioned on any tutorials is that the MTK6589 is different to how you flash other mediatek devices with SPFlashTool; why? Because you MUST put the battery back in before you flash unlike other MTK devices where they explicitly say DO NOT put it in and/or that  you should flash without the battery in place. THIS IS INCORRECT!

Next thing to emphasise is this: You must have the phone disconnected when you click on the download button inside SPFlashTool. You press download then you put the battery back in your phone with the USB connected to the phone., wait and when the download part finishes (only a few seconds) THEN you plug the phone in to the computer (yes with the battery still in place) but do not switch the phone on.
When the phone is detected by Windows and starts to load the drivers like it usually does and then disconnects...well what happens now is that when it loads drivers for a second SPFLashTool engages the phone and holds open the connection. It will pause for a couple of seconds (but you will notice it doesn't disconnect) and then SPFlashTool will show a red/orange progress bar that goes quickly....then it will write the firmware when you see the yellow progress bar.

Something to note here (I downloaded literally hundreds of drivers by the way) that you only need 1 driver and that is the one mentioned in the tutorial. 

You don't need to do all the bullsh!t with device manager and removing drivers etc with USBDview....this should only be if the phone doesn't read initially as MTK65xx preloader OR doesn't end up registering as  MediaTek DA USB VCOM. 

So I will explain...when you plug it in on a clean WIndows 7 PC for he first time it will appear as MTK65xx preloader under device manager under unknown device and Windows will attempt to download the correct drivers and then fail. This is normal. DO NOT GO AND INSTALL PDANET DRIVERS!!! This doesn't work. Yes the drivers ARE more stable and don't disconnect nearly as much as the other MediTek drivers, however what this does is register the devices as an Android ADB device, and allows you to use ADB. We want to use SPFlashTool, not ADB at the moment. Installing other MediaTek drivers after PDANet for some reason causes a conflict and interferes with communication with the device?? I suspect that this is what was causing much of the issues I was experiencing? You may use the PDANet drivers after you have flashed via SPFlashTool if you cannot get an ADB connection, however in my case once the new firmware was written to the device and it was restored and fully functional; when I plugged it in the ADB drivers loaded automatically anyway

Ok next points to make. Unplug your device. Install the drivers (I have attached the ones that worked for me). NOTE: You may need to log in allowing unsigned drivers as mentioned in other tutorials. To do this you can use EasyBCD, go into advanced settings for the Windows 7 bootmenu entry and allow the use of unsigned drivers and put a wait of say 10seconds on the menu count down (in stock form Windows has assigned 30 seconds but standard it bypasses the boot menu - this makes it harder to press the F8 key during boot up). After finishing in EasyBCD reboot and when you come to the Windows boot menu press F8 anyway and choose allow use of unsigned drivers. This is a just in case thing.
Get EasyBCD from HERE
Once in Windows, plug in your device WITH THE BATTERY IN and device switched off. Open Windows device manager (a quick way is type devmgmt.msc in Start menu or Run menu from the start menu - if you search for the management console by full file name you can right click the devmgmt.msc and pin it to the Start menu  this is what I have done).
In device manager you NEED to see the device registered as *MediaTek DA USB VCOM*. If it is not appearing push the volume up button + but keep the phone OFF. When it appears for just a second make sure it is MediaTek DA USB VCOM. **This is important** It must NOT be registered as Preloader or any other MediaTek driver ie.  Preloader USB VCOM port OR MediaTek USB VCOM (Android) etc. IT MUST BE *MediaTek DA USB VCOM* Just look for the one that has DA in the name and is a VCOM driver. This is the driver we want:good:





Ok here is where I will mention that USBDview removal of drivers is not necessary and does absolutely nothing anyway because Windows 7 remembers every single driver you have installed regardless of the fact that you have removed/uninstalled and even checked the box delete drivers or what ever. It doesn't matter...every driver you have ever tried will be in the device driver list. USBDview is only good for unregistering the device association with a registered driver. It doesn't remove drivers.

So now where was I? Ahh right, yep. When you plug in your device (switched off and the battery in place) and it appears momentarily in device manager it must be MediaTek DA USB VCOM, If not Or if it disappeared too fast; just push the volume up button again and this time as it appears quickly, click to expand the (PORTS COM &LPT) listing, then quickly right click the MediaTek listing and go to Update Driver Software. You may need to do this several times to get it. Unplugging the USB from the PC and plugging it back in again may help. Resist the urge to search for new drivers as the device IS actually detected but not as a PORTS COM &LPT, and doing so will be fruitless as you will only assign the incorrect drivers to the incorrect function. So unplug and replug it in again pressing volume up.
Note: It does not matter if the device disconnects and disappears out of Device Manager when you are in the Upgrade Device Driver software menu....this is normal.  The most important point here is that the correct driver is being registered to the correct device function (pressing the volume up button).
The device needs to appear as MediaTek DA USB VCOM and this must be registered specifically to the (PORTS COM &LPT) in device manager. If it lists elsewhere as a USB device and has the MediaTek DA USB VCOM driver assigned to it, then you need to uninstall the driver from the device listing and start again. Don't go looking for more drivers PLEASE!

*Click for explanation*



        Ok I will digress again for a moment to explain why all this is so important and what many of us are not realising especially with all the tutorials around; the important point here is that MediaTek devices may be listed many numerous devices in device manager and this is normal. They could be an ADB android device, a MediaTek USB Port version etc and these are not the functions we want to use for flashing with SPFlashTool are they? I know when I plug in my Galaxy S3 it loads at least 5 different drivers! Same with these devices.
*We need to have the (PORTS COM &LPT) registered as MediaTek DA USB VCOM and this ONLY achieved when we press the volume up button!!* If the device disappears from the list after plugging it in and appears as something else and then we register the MediaTek DA USB VCOM driver to this function we are likely trying to use the MediaTek DA USB VCOM driver to load the MediaTek USB Port function and this is obviously NOT the protocol that SPFlashTool is using to communicate with the device to write new firmware.
    


Ok I will continue now, once you have got into the Upgrade Driver Software menu, Go to_ 'Browse my computer for device software',_ Then select the second option _'Let me pick from a list of device drivers on my computer'_, just choose the_ 'show all'_ at the top of the list, Next you **should** see MediaTek DA USB VCOM listed in amongst various MediaTek drivers., select this one, However if you do not see MediaTek DA USB VCOM listed in the list there then uncheck the box next to_ 'Show compatible drivers' _and it should now show a few more drivers. You may need to scroll in the right menu bar down to MediaTek. 
You will be hit with an overwhelming list of MediaTek drivers!  funny how even the drivers you previously removed are included in that list eh?
Select the required MediaTek DA USB VCOM driver from the list. If its not there (then and only then) you should try install another set of drivers and restart the process again. Try the drivers I have attached below first though. 
At this point please resist the urge to click 'Have disk' then 'Browse' to and go scouting for a specific driver in the hopes that this will be the one; THIS IS WRONG! and should not be recommended like it is in just about every tutorial I have seen so far.

Once you have selected the driver as MediaTek DA USB VCOM and closed out of the menu you will notice that it has actually gone from the list in device manager? This is normal. The driver is only meant to appear when we do a specific thing and that is pressing the volume up button to write firmware using SPFlashTool and nothing else. As I mentioned earlier, this is by design. You will note that MediaTek devices, have these protocols USB Mass Storage, MTP, PTP, ADB and COM &LPT.

Now unplug your device. I would at this point do a reboot of Windows (again ensuring unsigned drivers by pressing F8 -  just incase) when you come back into Windows, open device manager again. Keep the device off and have the battery in. Plug the MicroUSB end into the device first (it's easier - trust me you will understand when I explain). Now keeping it switched off but press and hold the the volume up button and then plug the cable into the PC USB port; watch as it registers inside device manager as MediaTek DA USB VCOM. When it does, disconnect the cable from the USB port. 
Now Open SPFlashTool. Select the scatter file. Then uncheck the following from the list (Preloader, MBR1, EBR1, Uboot, Sec_Ro, Logo, EBR2 and FAT - note fat is for the internal sdcard). We want to write to system, recovery and boot pretty much.
Keep the device UNplugged. Click the download button.  You will see the purple progress bar but for only a very brief moment. This is ok and is normal.
Now we do as we did before. Plug the MicroUSB end in first to your device. Have it switched off but with the battery in place. Press and hold the volume up + button and then plug the cable in to the PC USB port again. At this point you will hear the device register with Windows as you normally would however you should notice that it doesn't disconnect straight away like it normally does? This is because the MediaTek DA USB VCOM is registered to the PORTS COM &LPT and SPFlashTool is listening on this port. 
Then shortly after progress with a Red/Orange bar. Then it will pause for a what seems like a long time.....leave the device plugged in!
Once you see the yellow progress bar you can breath with relief. Congratulations you have just revived your bricked device :good:


----------



## gauravkr (Mar 5, 2015)

*link?*



Jarmezrocks said:


> Hey guys,
> 
> Guess what?! I FOUND THE ANSWER!!! The disconnect is by design. The device is not actually meant to stay connected. I will explain why later but first I will direct you towards the correct information to get you back up and running again.
> 
> ...

Click to collapse



can you give us the link of the drivers you used? because every driver i have is preloader, not DA.


----------



## Droid-KE (Mar 27, 2015)

*Mediatek DA VCOM Port disconnects*

Hi

I tried below and actually get the phone registered as Mediatek DA VCOM Port but it still disconnects when I connect after hitting download in SP Flash Tool and faile with error (2004)






Jarmezrocks said:


> Hey guys,
> 
> Guess what?! I FOUND THE ANSWER!!! The disconnect is by design. The device is not actually meant to stay connected. I will explain why later but first I will direct you towards the correct information to get you back up and running again.
> 
> ...

Click to collapse


----------



## greenro (Apr 20, 2015)

*Error 2004*

I am getting BROM ERROR : S_BROM_DOWNLOAD_DA_FAIL (2004). I tried different USB ports, 2.0 and 3.0 and different PCs(I also tried with windows XP and Windows XP drivers). After I press download and connect the phone, SP-FlashTool won't "catch" the MediaTek PreLoader USB VCOM Port. It will disconnect and connect every 2 seconds, for 9 seconds, then it will give me that error.  I couldn't make that port a MediaTek DA USB VCOM Port.
If anyone has an idea of what can I do to fix this, please tell me.
EDIT: Solved by renaming "checksum.ini" to "checksum.old"


----------



## boecima (Jul 23, 2015)

Thanks mate, finally founded the solution  whit the battery trick flashtool do wht has to do and THEN disconnect..

 it is not the solution of my problem but is a big step ,  maybe you can help me , my problem is that my phone since back from US seems to have issue whit frequencies, I have line only every 20 meter , i mean if i walk for 10 meter i have full bar , next 10 little or no signal , i go back and have full bar ,  reading here and there could be the baseband, i have  one for my jiayu g4b but dont know how to upload it whit flash-tool  .


----------



## Wozik (Sep 18, 2015)

Jarmezrocks said:


> Once you see the yellow progress bar you can breath with relief. Congratulations you have just revived your bricked device :good:

Click to collapse



Many thanks for this detailed description! I restored my device back from the dead. It was totally blacked out.

One thing that differs: I didn't see MediaTek DA USB VCOM in my device manager. It was either USB COM or MediaTek Preloader USB. Still I started to connect/disconnect the device and pressing "Download" button in Flash Tool as soon as the Preloader driver appeared. All of a sudden it changed to MediaTek DA USB VCOM and it worked like a charm!

Thank you so much!


----------



## shomitverma (Oct 28, 2015)

*same problem of connectivity*

What about the phonea whos battery cant be removed ..ed micronax a350 aka knight


----------



## akhil1245 (Dec 3, 2015)

*thankssssssssssss friend*

@Jarmezrocks
thank you very much friend I have upgraded firmware of my phone


----------



## uramino (Jan 3, 2016)

my acer iconia b1-710 is stuck in android robot, "formating/data, i tried spft and all the things i have found on internet,  i have MediaTek DA USB VCOM, but it disconnect every 2 seconds i reconected to my pc, i didnt see the purple bar, it disconnect in the red one. help please.


----------



## deb.sen93 (Jan 26, 2016)

*[Solved] Its just a driver issue.*



Sohan_Saymum said:


> I am trying to upgrade my Canvas HD 20 Android 4.2.1. But, everytime I connect the phone with my pc, the "MTK6589 USB Vcom port" appears for only 2 second in the device manager, then it's gone. And the "Device Disconnect Sound" is played. So, I cant flash the ROM. what's going wrong? I have followed every steps in this tutorial.
> http://forum.xda-developers.com/showthread.php?t=2308431
> 
> .....
> ...

Click to collapse



Install Mediatek Usb Preloader Vcom Port Driver. Follow the instruction here. http://www.yomitech.com/2015/04/how-to-install-mediatek-usb-preloader.html.

Then flash.


----------



## Chrisgia (Feb 20, 2016)

Hey guys!

I don't find the solution to my problem. I am trying to unbrick my HTC Desire 310 (MT6582), but I always get the same error S_BROM_DOWNLOAD_DA_FAIL (2004).. I've tried deleting and reinstalling drivers, also did everything in Jarmezrocks's solution, changed USB ports, and so on but I never get the MediaTek DA USB VCOM driver, I always get the MediaTek PreLoader USB VCOM Port driver instead.

I'm running on x64 Windows 10.

Does anyone have a solution to this problem?

I would highly appreciate if you can help me for this.

Thanks!


----------



## Chrisgia (Feb 28, 2016)

Really No one ?


----------



## red john 07 (Mar 21, 2016)

Jarmezrocks said:


> Hey guys,
> 
> Guess what?! I FOUND THE ANSWER!!! The disconnect is by design. The device is not actually meant to stay connected. I will explain why later but first I will direct you towards the correct information to get you back up and running again.
> 
> ...

Click to collapse



Hello bro thank you very much for your great work here I just want to say that I correctly flashed my device with SP flash tool without the vcom USB drivers because my device detected as a preloader mtk  device and I flash it without the battery at it means I remove the battery before I flash it and it's correctly flashed and I use it now


----------



## omid (Apr 1, 2016)

*Installing da driver*



gauravkr said:


> can you give us the link of the drivers you used? because every driver i have is preloader, not DA.

Click to collapse



WELL YOU CAN MAKE IT BY :
Turn Off the device
Open Up device manager
double click on PORTS (COM & LPT)
connect the device
IF It's recognized as MTK preloader 65XX  under a newly created category ( I can't remember the title of category, but it's in the middle of list) >>> JUMP TO BELOW (SKIP FOLLOWING 4 LINES)
[[[[ IF It's recognized as preloader usb vcom under PORTS (COM & LPT) >> AND SHORTLY WILL DISAPPEAR
before it disappears
immediately right click on it and click uninstall, tick the box, apply , ok ]]]]
NOW AS YOU DISCONNECT  & RECONNECT YOUR DEVICE it's recognized as MTK PRELOADER 65XX
anyway the MTK PRELOADER 65XX is also disappeard shortly
before disappearing right click on it, choose update, browse my computer.. , pick from a ... , browse for driver, and select the driver you have, UNTICK show only ..., double click MTK DA VCOM driver (FIRST ONE) APPLY OK.
NOW WHEN YOU DISCONNECT AND RECONNECT YOUR DEVICE it's recognized as DA. under PORTS CATEGORY.

HOWEVER I HAVE ALREADY DONE THE PROCEDURE AND NOTHING BUT ERROR 6045

---------- Post added at 10:49 PM ---------- Previous post was at 10:27 PM ----------




Chrisgia said:


> Really No one ?

Click to collapse



you first HAVE TO DO IS TO DISABLE > THE DRIVER SIGNING <

SImply you have to enter advanced menu of boot/startup options

*** in windows 7

1. During boot-up, continuously press <F8> to get to Advanced Boot Options. Note: On some systems, you need to first press <F2> to go into Boot Menu, then press <F8> to reach Advanced Boot Options.

2. When the menu appears, use the DOWN arrow key to scroll to “Disable Driver Signature Enforcement.”

3. Press <Enter>.

4. Continue the boot process.

5. After your computer has completed the boot process, please install the drivers per the included instructions.

*** in windows 8 or 10
HOLD SHIFT KEY
CLICK RESTART FROM START MENU
after restart and start up you will go to a blue window
click troubleshoot
click advanced option
click startup option
click restart
after boot up
press  7 to disable driver signing

---------- Post added at 11:24 PM ---------- Previous post was at 10:49 PM ----------




Chrisgia said:


> Really No one ?

Click to collapse



you first HAVE TO DO IS TO DISABLE > THE DRIVER SIGNING <

SImply you have to enter advanced menu of boot/startup options

*** in windows 7

1. During boot-up, continuously press <F8> to get to Advanced Boot Options. Note: On some systems, you need to first press <F2> to go into Boot Menu, then press <F8> to reach Advanced Boot Options.

2. When the menu appears, use the DOWN arrow key to scroll to “Disable Driver Signature Enforcement.”

3. Press <Enter>.

4. Continue the boot process.

5. After your computer has completed the boot process, please install the drivers per the included instructions.

*** in windows 8 or 10
HOLD SHIFT KEY
CLICK RESTART FROM START MENU
after restart and start up you will go to a blue window
click troubleshoot
click advanced option
click startup option
click restart
after boot up
press  7 to disable driver signing


----------



## Sohan_Saymum (Mar 8, 2014)

I am trying to upgrade my Canvas HD 20 Android 4.2.1. But, everytime I connect the phone with my pc, the "MTK6589 USB Vcom port" appears for only 2 second in the device manager, then it's gone. And the "Device Disconnect Sound" is played. So, I cant flash the ROM. what's going wrong? I have followed every steps in this tutorial. 
http://forum.xda-developers.com/showthread.php?t=2308431

.....
I have Tried in different PCs and with different Data Cables. But same problem exists. And, I had no problem with this cable while sharing files with my pc. I used this cable for Mass Storage.
I figured that, the connection problem I have described previously is the main cause of this mess. can anyone help me out with this?????


----------



## E66666666 (May 2, 2016)

Well, the little **** didn't get detected by the flashing tool for me, it kept disconnecting upon download. It somehow kept the connection open when doing an FW upgrade though, so that's nice. Flashed the stock ROM successfully this way.


----------



## warhead619 (May 26, 2016)

niki_help said:


> Hello,
> I have the same problem. I did everything discribed in forums. The driver of MT Preloader Vcom port is installed correctly.  I tested with different cables and different OS (XP and Windows 7 32 bit) and differenet computers.... SP Flash Tool says that:
> BROM ERROR : S_BROM_DOWNLOAD_DA_FAIL (2004)
> [H/W] Fail to download DA to baseband chip's internal SRAM
> ...

Click to collapse


----------



## kaesha4 (Jun 4, 2016)

E66666666 said:


> Well, the little **** didn't get detected by the flashing tool for me, it kept disconnecting upon download. It somehow kept the connection open when doing an FW upgrade though, so that's nice. Flashed the stock ROM successfully this way.

Click to collapse



How did you do that? I'm using YGDP to download FW to my phone. It went well at first, but always disconnected at 98% of the CPB download process. Probably it was caused by the phone that registered as MediaTek PreLoader USB VCOM Port in Device Manager, but after I uninstall the driver, update driver using MediaTek DA USB VCOM Port, unplug the phone and plug it in again, it still registered as MediaTek PreLoader USB VCOM again.


----------



## Mollooxx (Jun 13, 2016)

*Look at here!*



Sohan_Saymum said:


> I am trying to upgrade my Canvas HD 20 Android 4.2.1. But, everytime I connect the phone with my pc, the "MTK6589 USB Vcom port" appears for only 2 second in the device manager, then it's gone. And the "Device Disconnect Sound" is played. So, I cant flash the ROM. what's going wrong? I have followed every steps in this tutorial.
> http://forum.xda-developers.com/showthread.php?t=2308431
> 
> .....
> ...

Click to collapse



---------------------------------------------------------------Answer-------------------------------------------------------------------------
For that it stabilize press all button or the two volume button + power;
Try that with battery, if it doesn't run, try with battery.
After the "Red bar" (on SP flash tool) you release the buttons.


----------



## reis1996 (Jun 23, 2016)

*did what you said but still need help*



Jarmezrocks said:


> Hey guys,
> 
> Guess what?! I FOUND THE ANSWER!!! The disconnect is by design. The device is not actually meant to stay connected. I will explain why later but first I will direct you towards the correct information to get you back up and running again.
> 
> ...

Click to collapse



so when i open my device manager it show two ports in Ports(COM & LPT)
1. mediatek da usb vcom port (com5)---has yellow triangle for unrecognized 
2.mediatek preloader usb vcom port (com3)

my issue is when i use spf tools at the bottom right corner only "mediatek preloader usb vcom port (com3)" is visible now it doesnt work when i click download or firmware upgrade it just stays there with the option to click stop available. however if i pull out the cable from the device now an error appears on spf tools saying it was unplugged. i waited for 10mins spf tools is not doin anything. HELP!!!! I WILL DONATE!!!


----------



## koustav00 (Sep 3, 2016)

Thanx man.. Worked like a charm!!!


----------



## azimjasir (Sep 9, 2016)

same problem me too........


----------



## metal_icaruz (Nov 4, 2016)

*Update*

1. Start the fhasing tool.
2. Press download, wait for 2-3 seconds.
3. Connect your device.
4. The update will resume now.



Sohan_Saymum said:


> I am trying to upgrade my Canvas HD 20 Android 4.2.1. But, everytime I connect the phone with my pc, the "MTK6589 USB Vcom port" appears for only 2 second in the device manager, then it's gone. And the "Device Disconnect Sound" is played. So, I cant flash the ROM. what's going wrong? I have followed every steps in this tutorial.
> http://forum.xda-developers.com/showthread.php?t=2308431
> 
> .....
> ...

Click to collapse


----------



## Carly2.0 (Feb 12, 2017)

*Why the MTK 6589 USB Vcom port disapear after 2 second?*

I had this same problem recently.
The solution is when you hear the phone connects to the computer quickly insert the battery into the phone. You have to be very fast for it to work.


----------



## rgnr (Feb 18, 2017)

*Fail!!!*

Having the same SH** for about three months now. No matter which driver is registered, DA or preloader, the phone just keeps disconnecting every 2 secs, thus download fails. The device is 6735 based, Doogee Valencia 2 Y100 Pro.


That is so enraging!


----------



## georgepat (Apr 16, 2017)

Hi all...
I had problems to connect also but I was also having the message "pmt changed for the rom it must be downloaded" I was struggling several hours until i searched for it.
The answer came from https://www.leakite.com/2016/06/fixed-pmt-changed-for-rom-it-must-be.html

In SP Flash Tool interface, click Format tab
Once in Format tab, click Start to format the phone
Now go back to Download tab 
Load scatter file of the firmware you wish to flash
Click Download and connect phone.
Flashing should now commence.


----------



## Kingkon963 (Apr 25, 2017)

greenro said:


> I am getting BROM ERROR : S_BROM_DOWNLOAD_DA_FAIL (2004). I tried different USB ports, 2.0 and 3.0 and different PCs(I also tried with windows XP and Windows XP drivers). After I press download and connect the phone, SP-FlashTool won't "catch" the MediaTek PreLoader USB VCOM Port. It will disconnect and connect every 2 seconds, for 9 seconds, then it will give me that error.  I couldn't make that port a MediaTek DA USB VCOM Port.
> If anyone has an idea of what can I do to fix this, please tell me.
> EDIT: Solved by renaming "checksum.ini" to "checksum.old"

Click to collapse



will you pls explain me how you overcome the issue?
where can i find the "checksum.ini"?


----------



## ValterZz (May 31, 2017)

I have similar problem, my phone will not stay connected , it just disconnects every 5 seconds , and i cant use flash tools because of this   and on top of all windows auto installs mtk drivers and wont let me install them manually.


----------



## D-i-n-e-s-h (Jun 20, 2017)

*Edit option.ini in FlashTool folder*

In option.ini file, use following configuration in section Conn :

[Conn]
Type=1
DAPreLoader=false
USBHighSpeed=true
SupportAutoDetect=true
Battery=0
Timeout=3

Also follow steps mentioned comment #7 :
Turn off your phone, remove the battery then replace it after some seconds (and don't turn on the phone).
Press F9 (or hit Download button) OR Formate All + Download button(depending on your requirement) then
connect your phone into the computer via USB data cable. 
The process will start and a red progress bar will appear.

In right bottom of your tool GUI, you can verify that USB option is with auto detect.

This worked for me as 2 secs were enough for tool to detect USB Vcom port.


----------



## Hafizbenito (Jul 17, 2017)

Try to make usb autoboot or buy miracle magic boot or make usb modified boot


----------



## an2julian (Dec 26, 2017)

*guys fck this error , the only simple solution for device plug and unplug for a secon*

just format the device on tab format in spflash tool.
-unplug your device frst
-click start on format, then plug your device
completely follow steps on this video
*i'm new cannot insert outside link
-search on google "pmt changed for the rom it must be downloaded solusi"
-view the video on youtube with title "Cara mengatasi PMT changed for the ROM; it must be downloaded....."
uploaded by alltutorial.net
Published on Sep 2, 2015

and my phone flashed, with thread on miui(dot)com 
with title " [Tools, Tips & Tutorials] [MIUI Device Team] How to Flash Fastboot ROM with SP Flash Tool on Redmi Note 3G "

thanks hope it works.


----------



## markbeljoi (Feb 15, 2018)

*driver issues with phone software*

to sum it all up eveyone is being bullshited with these so call solutions posted all over the net, in a nutshell all these phone tools software is a load of crap,each and everyone has a driver problem, next you will be told to purchase a i7 pc, and still it wont work


----------



## Vinayakrg (Apr 15, 2018)

*preloader or "MediaTek DA USB VCOM" disconnecting*



Jarmezrocks said:


> Hey guys,
> 
> Guess what?! I FOUND THE ANSWER!!! The disconnect is by design. The device is not actually meant to stay connected. I will explain why later but first I will direct you towards the correct information to get you back up and running again.
> 
> ...

Click to collapse



Name Vinayak Email : [email protected]
Hi With Great interest i have read your solution to the connection disconnected in 2 seconds for pre loader.
more than 10 times

Ok I have used ur instructions one by one and executed it.
but still having problem of disconnection. i have did this in 4 different ways.
Drivers used: 1. Signed: MTK_USB_All_v1.0.8 (Seems Original, yes off course),
signed means the "DA USB VCOM"
2. Unsigned: drivers included in stock rom.
signed means the "MediaTek DA USB VCOM" (your told / said driver)

ok just have a look what i have did in 4 cases.
in every case pc win7 is booted in >>>> 'allow unsigned drivers'.

case 1. at first i have installed the signed drivers but it was assigned as preloader.
->>>> a) (without pressing + volume key )
here as u said i connect the phone Micromax a210 mtk6589 turned of with the battery.
The device manger is already opened, immediately gone for update driver. then selected signed "DA USB VCOM" Driver.
Which was installed earlier.

Method for update of hardware driver.
Update Method / Trick : Here at every time, whenever you go to update driver, after selecting the appropriate driver.
for example if i want to change "preloader" to "DA USB VCOM"
Click as :>>> Update driver(in less than 2 seconds : yes done)    then click >>>>    Let Me Pick the driver
then >>>>    Ports (COM & LTP)   then >>>>   remove the tick from the box that means 'Show Compatible Hardware' and it will list all the all drivers (or both the drivers Signed and Unsigned) related to Port (Com & LTP)(Protocol)
Then select the needed driver for installation.
Here is the trick at every time you change the driver.
at this time connect the mobile and immediately when or at the connection sound beeps hit the next.
(in case of unsigned driver it will again ask, do you want to install the unsigned drivers immediately click yes)
after clicking next or yes at this time it will again accepts the hardware for change and change/updates its driver.
this is very fast just in 2 seconds and at the time of clicking the next or yes. 1 second is almost gone.
Result : Diver is updated successfully. (in all 4 cases)

ok case 1 continued : so i updated to Signed Driver "DA USB VCOM".
now at the time of sp flash tool. here i wanted to only flash i.e. to download only the original recovery /stock recovery.
into the mobile, removed rest all ticks and only selected recovery.img for flashing.
Then clicked >>>> Download button.    Then >>>>    the bricked Micromax Phone, battery inserted, and connected to the usb.

The result of case 1 : after connection it shows but in 2 seconds it disconnects it.
And in sp flash tool error : red bar appears then pmt changed for the rom

similarly Case 2 : (for Signed driver)
b) (pressing + volume key ) during the driver update connection of phone
with pressing and holding Volume + (Up) Button for while.
after rebooting and checking it again disconnects the phone.
again tried with sp flash tool clicked download and connected the phone holding the volume plus button.
again disconnected
Case 2 Result : connection terminated, and in sp flash tool red bar appears then pmt changed for the rom

similarly Case3 : (for unsigned driver)
a) (without pressing + volume key ) "MediaTek DA USB VCOM" driver updated successfully.
in simple USB connection the connection is terminated.
then tried with sp tool again same disconnected problem appeared.
Case 3 Result : connection terminated, and in sp flash tool red bar appears then pmt changed for the rom

Case 4 : for unsigned driver
b) (now pressing + volume key )
 "MediaTek DA USB VCOM"
1.	holding volume Plus Button continuously until the driver gets updated successfully.
2.	Then as you said the rebooted and re checked with holding the Volume Up (Vol +) Button. still failed.
the "MediaTek DA USB VCOM" from device manager again disconnected. 
3.	now with sp flash tool clicked download, holding vol + again after 2 seconds disconnected.
case 4 result : same :  connection terminated, and in sp flash tool red bar appears then pmt changed for the rom

please help contact me at [email protected]


----------



## trongthanht3 (Jul 29, 2018)

Hi
I have same problem but my Wiko rainbow up can not remove battery so I can't turn off my phone or remove battery and plug again. I need help.
Sorry for my bad english


----------



## asdx2 (Aug 11, 2018)

im trying to flash tab cant remove battery same problem any solution?


----------



## Sohan_Saymum (Mar 8, 2014)

I am trying to upgrade my Canvas HD 20 Android 4.2.1. But, everytime I connect the phone with my pc, the "MTK6589 USB Vcom port" appears for only 2 second in the device manager, then it's gone. And the "Device Disconnect Sound" is played. So, I cant flash the ROM. what's going wrong? I have followed every steps in this tutorial. 
http://forum.xda-developers.com/showthread.php?t=2308431

.....
I have Tried in different PCs and with different Data Cables. But same problem exists. And, I had no problem with this cable while sharing files with my pc. I used this cable for Mass Storage.
I figured that, the connection problem I have described previously is the main cause of this mess. can anyone help me out with this?????


----------



## celvdd (Aug 11, 2018)

*This works!*



Carly2.0 said:


> I had this same problem recently.
> The solution is when you hear the phone connects to the computer quickly insert the battery into the phone. You have to be very fast for it to work.

Click to collapse



Thank you! This worked! I had to try it like 20 times, you need to be very fast indeed.
1. Start Flash Tool and add scatter file
2. Click Download
3. Connect phone without the battery and insert the battery from the moment you hear the connection sound, it needs to be immediately.


----------



## Donphillipe (Sep 28, 2018)

To more easily update drivers for devices "disappeared" from the device manager, you can do this.
- create a Windows text file renaming it to "DeviceManagerHidden.bat" and add this to the file:
    echo off
    SET DEVMGR_SHOW_NONPRESENT_DEVICES=1
    START devmgmt.msc 

Now double click this bat file to execute it (you may need administrator authority) and then in Device Manager when you click "View" and "Show hidden devices" you can see the Ports selection and open it and work with selecting other drivers for anything listed here.   

 I couldn't get mine to stay switched after selecting a different one, however.   There were 3 selections for the Mediatek DA USB xxxxx option, one with a 2.xxx.xxx suffix, one with a 3.xxx.xxxx suffer and one with a simple word "Port" as a suffix.    None of the selections I made held through a reboot, nor did they register with a name change when I attempted to update the driver for Media Tek PreLoader USB VCOM (Android) (COM11)


----------



## Jexboxer (Aug 5, 2019)

I have the same problem. 
*No display. 
No Light. 
USB On and Off sound.  *
Except I can flash with SP Flashtool 100% Green Check.
But the phone will not turn on. I have my old Karbonn Sparkle V MT6582.
Even with the batery the phone I get USB on and off sound.
The RAM Test shows ok.
 EMMC Shows error because it won't boot. If EMMC was bad why the heck would it flash 100% at 15Mb/s ?  
How it went bad? Well one day I was trying to move files from my sd card to internal drive or the opposite.. and it was giving me read error.. and apps were crashing.. I tried rebooting it.. still problem. 
So I used SP flash tool with original Stock ROM. and then it died. But I had used the same ROM before and there were no problems. So what is causing this idk? Went to the repair shop. He said EMMC need replacement because why not to loot the customer? anyways I know its not EMMC because it writes well. 
Possible the Reading is the issue. It can't read.
Any idea what could be the cause?
If nothing works I am gonna cook the motherboard in the oven.. 
Anyone have any solution I would be glad to know.


----------



## Droidriven (Aug 5, 2019)

Jexboxer said:


> I have the same problem.
> *No display.
> No Light.
> USB On and Off sound.  *
> ...

Click to collapse



This is common, it is a matter of timing and/or a matter of doing things on the correct order.

Sent from my SM-S767VL using Tapatalk


----------



## Mashjm (Dec 14, 2019)

Hi everyone, those having the connection and disconnection loop should try using both sp flash tool and miracle box. Since miracle box won't hold on to the connection, start by using sp flash tool just load what you wanted to do to the phone and then click on the necessary button but don't connect the phone, go to miracle box and select what you wanted to do then click on start, insert the battery to the phone and connect the USB cable. Hope this will work for those in need since it works for me. Miracle box will fix your issue since sp flash tool will most likely pop-up an error but it will help in keeping the connection alive for miracle box to do it's work.


----------



## xchaoling (Mar 13, 2020)

Jexboxer said:


> I have the same problem.
> *No display.
> No Light.
> USB On and Off sound.  *
> ...

Click to collapse



my Fake Table P10 zh960 MT6582 is in this condition, I try several roms with the correct name and despite completing the loading of the rom has not yet returned to work, I believe I still have not hit the rom, but I tested more than 30 and I'm almost giving up


----------



## DHANOLA (Jun 8, 2021)

Jarmezrocks said:


> Hey guys,
> 
> Guess what?! I FOUND THE ANSWER!!! The disconnect is by design. The device is not actually meant to stay connected. I will explain why later but first I will direct you towards the correct information to get you back up and running again.
> 
> ...

Click to collapse



Hey there I have followed your guide and have the drivers shown ad Mediatek  DA USB VCOM but then also it stays in device manager for 2 seconds only and gone but the SP Flash tool doesn't detect it and the download doesn not start .I have my Ralme U1 phone hard bricked and unable to turn on and  not Even it is detecting the charger. Please Help!!!!


----------

