There are 3 known scenarios that could cause your Mediatek Android phone to go dead and not even respond to charging or the power button. We have so far dropped guides on fixing two scenarios which are:
1. Corrupted, wrong or missing Preloader.bin: The phone could go totally dead when preloader.bin gets corrupted on its own, you flash a wrong preloader.bin, or format in SP flash tool without flashing back the firmware to the phone. See the guide @ https://forum.hovatek.com/thread-286.html for how to fix this
2. Interrupting SP flash tool during flashing: The phone could go totally dead when there's some kind of interruption during SP flash tool flashing. This could be as a result of you shaking the USB cord, disconnecting due to a slow flashing or SP flash tool popping up an error. See the guide at https://forum.hovatek.com/thread-808.html for how to fix this.
Scenario 3 is different from 1 & 2. Some users of Tecno D5 and Infiinx Not 2 X600 would be familiar with this. In this case, the phone goes totally dead after successfully flashing an incompatible firmware. The fixes for scenario 1 and 2 do not work for scenario 3.
Ensure you have properly tried the fixes for scenario 1 and 2 before considering scenario 3 as you could damage your phone for good if done wrong
To fix scenario 3, you'll need to join 2 points on the phone's Mother Board then connect the phone to PC via USB cord for flashing.
* Install VCOM drivers on the PC (see https://forum.hovatek.com/thread-440.html)
* Loosen the phone till you get to the Mother Board (The procedure varies with phones so lookup yours)
* On the Mother Board, locate two golden points named GND and KCOLO (see the two red arrows in the image below )
* Solder a thin wire to the GND point then join it to the KCOLO point
* Connect the phone to the PC via a USB cord just to test; the PC should now recognize it and make a sound.
* Disconnect the phone then flash the right firmware using SP flash tool @ https://forum.hovatek.com/thread-159.html
* Disconnect the wire from the Mother Board after flashing
See the video tutorial below or @ https://youtu.be/jPn4FBAHib0
Credits to Benzalf for sending in the video clip