source: link here
be sure to visit the link for nice tutorial pics to assist you
Support Onda V972,v971 Quad Core,V812,V811 Quad Core
1.Please put the Micro USB cable in the desktop on the rear of the USB interface
2.Ensure the tablets power more than 70%
3.If you tablet can be turn on, please update the firmware through OTA.
4.Make sure your tablet is turn off, please hold the power button for 10-20 seconds to make sure your tablet is turn off.
1.Download the firmware form (http://www.onda-tablet.com/news/
2.Unzip the downloaded firmware package
3.Install the update tool ,double click to install.
4.Run the firmware upgrade tool
Please make sure your tablet are shut Down. If you can't determine whether in the shutdown state, Hold the power button for 10-20 seconds
Please Hold the Home button (the button with small house icon),Connect your Micro USB Cable and short press the power button for 5-10 times in a row to computer tips found new hardware, release the home button.
1.Before update, please backup the tablet inside the store of useful data, if the machine have a TF card, please pull out the TF card;
2. Please read carefully the instructions before update, flash risks, improper operation caused tablet computer can't use, need to contact your buyers to return to factory for maintenance treatment.