UltraDuo Z2 Firmware Update

Make sure your SD card is formatted and copy the SPHOST.BRN into the root directory of the SD card. 
Notice: Make sure the file name is SPHOST.BRN If you see SPHOST(1) .BRN or so on, please rename the file name to SPHOST.BRN

Insert the SD card into the dashcam.

Connect the UltraDuo Z2 to your PC or Mac with the USB cable, and make sure the dashcam is charging. IF YOUR DEVICE DOES NOT HAVE ENOUGH POWER, IT MAY CAUSE THE UPDATE FAILURE.

When turning on the dashcam, there will be a popup message "USB Storage, Dash Cam" and select "Dash Cam" then press OK button.

Another popup message "Firmware update: Yes, No" select "Yes" then press OK button.

It may take a while for updating. Once it finishes the update, it will turn off the device automatically. DO NOT TURN OFF OR PRESS ANY BUTTON DURING THIS PERIOD, IT MAY CAUSE THE UPDATE FAILURE.

After updating, delete the SPHOST.BRN of the SD card or format the SD card on the device. 

Press MENU button twice to entry Setup Menu and select the "System Info" and select "Firmware Version." If the Version is Z2_3.5_AHAZBC_B, then it is successfully updated.