Download Android 4.4.2 stock firmware v.20170418 for Allwinner T3 K2101 Car DVD from here or from here. Download Android 4.4.2 stock firmware v.20171026 for Allwinner T3 K2101 Car DVD from here or from here.
Archive name: Allwinner T3 K2101_JSH_S212102.20170418 / Allwinner T3 K2101_JSH_S212102.20171026
Image: update.zip / update.zip
Archive file size: 501 MB / 555 MB
Platform: Allwinner A33
Build number: t3_p2-eng 4.4.2 KOT49H 20170405 test-keys / t3_p2-eng 4.4.2 KOT49H 20171013 test-keys
Caution: Please do not update firmware unless you know what you are doing, you really want it or it is absolutely necessary. Firmware updates may occasionally have bad results, like bricking your device, temporarily or permanently. The firmware update process is done entirely at your own risk. Before attempting to update the firmware, back up your data.